Apparatus and Method for Uplink Power Control For A Wireless Transmitter/Receiver Unit Utilizing Multiple Carriers

ABSTRACT

A method and apparatus for determining uplink power in a wireless transmit receive unit (WTRU). The WTRU operates in a carrier aggregated system. The WTRU is configured to receive a plurality of uplink power parameters indexed to one of a plurality of uplink carriers and receive a transmit power control command indexed to the one of the plurality of uplink carriers. The WTRU is configured to determine a pathloss of the one of the plurality of uplink carriers and determine a transmit power for the one of the plurality of uplink carriers based on the plurality of power parameters, the transmit power control command, and the pathloss.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Nos.61,151,174, filed Feb. 9, 2009, 61/152,351 filed Feb. 13, 2009 and61/234,226, filed Aug. 14, 2009, which are incorporated by reference asif fully set forth herein.

FIELD OF INVENTION

This application is related to wireless communications.

BACKGROUND

Wireless communication systems may use many techniques to increasethroughput and user services. One such technique is carrier aggregationand support of flexible bandwidth. Another technique is to transmit bothuplink data and control channels simultaneously. For example, in anadvanced long term evolution (LTE-A) compliant system, uplink (UL)channels may be transmitted simultaneously, such as the physical uplinkshared channel (PUSCH) and physical uplink control channel (PUCCH).

Carrier aggregation adds complexity to transmit power control schemes ina wireless transmit receive unit (WTRU). A base station, such as aneNodeB (eNB), for example, may have much of the information required fora WTRU to determine its UL power requirements. In single carrier system,the eNB can give the WTRU that information when it gives the WTRU otherinformation. For example, the eNB may provide the WTRU with UL powercontrol configuration data when providing the WTRU with an UL grant.However, when multiple carriers are used and simultaneous transmissionof uplink control and data channels is implemented, the WTRU may receiveuplink configuration information that is complex. A WTRU may performcomplex operations to properly control UL transmission power.

SUMMARY

A method and apparatus for determining uplink power in a wirelesstransmit receive unit (WTRU) are disclosed. This may include operatingthe WTRU in a carrier aggregated system. This may also include the WTRUreceiving a plurality of uplink power parameters indexed to one of aplurality of uplink carriers and receiving a transmit power controlcommand indexed to the one of the plurality of uplink carriers. The WTRUmay determine a pathloss of the one of the plurality of uplink carriersand determine a transmit power for the one of the plurality of uplinkcarriers based on the plurality of power parameters, the transmit powercontrol command, and the pathloss.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1 shows an overview of an Evolved Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access Network(E-UTRAN);

FIG. 2 shows a wireless communication system including a plurality ofwireless transmit receive units (WTRUs) and an e Node B (eNB):

FIG. 3 is a functional block diagram of the WTRU and the eNB of thewireless communication system of FIG. 2;

FIG. 4 shows an overview of a wireless communication system usingcarrier aggregation with contiguous carriers in accordance with anembodiment;

FIG. 5 shows an overview of a wireless communication system usingcarrier aggregation with non-contiguous carriers in accordance withanother embodiment;

FIG. 6 is a signal diagram for a method of power control in accordancewith an embodiment;

FIG. 7 is signal diagram showing a power control method in accordancewith another embodiment;

FIG. 8 is a flow chart showing a power control method in accordance withan alternative embodiment;

FIG. 9 is a flow diagram of a method of power control in accordance withanother alternative embodiment; and

FIG. 10 is a flow diagram of a method of power control in accordancewith yet another alternative embodiment.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

FIG. 1 shows an overview of an Evolved Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access Network(E-UTRAN) 100 in accordance with the prior art. As shown in FIG. 1,E-UTRAN 100 includes three eNodeBs (eNBs) 102, however, any number ofeNBs may be included in E-UTRAN 100. The eNBs 102 are interconnected byan X2 interface 108. The eNBs 102 are also connected by an S1 interface106 to the Evolved Packet Core (EPC) 104. The EPC 104 includes aMobility Management Entity (MME) 112 and a Serving Gateway (S-GW) 110.Other network configurations may be used, and nothing disclosed hereinis limited to any one particular network configuration or architecture.

In a wireless communication system, a wireless transmit receive unit(WTRU) may communicate with an e Node-B (eNB). FIG. 2 shows a wirelesscommunication system 200 including a plurality of WTRUs 210 and an eNB220. As shown in FIG. 2, the WTRUs 210 are in communication with the eNB220. Although three WTRUs 210 and one eNB 220 are shown in FIG. 2, itshould be noted that any combination of wireless and wired devices maybe included in the wireless communication system 200.

FIG. 3 is a functional block diagram 300 of the WTRU 210 and the eNB 220of the wireless communication system 200 of FIG. 2. As shown in FIG. 2,the WTRU 210 is in communication with the eNB 220. The WTRU 210 isconfigured to transmit and receive on a single carrier or on multiplecarriers. The carriers may be contiguous or non-contiguous.

In addition to the components that may be found in a typical WTRU, theWTRU 210 includes a processor 315, a receiver 316, a transmitter 317,and an antenna 318. The WTRU 210 may also include a user interface 321,which may include, but is not limited to, an LCD or LED screen, a touchscreen, a keyboard, a stylus, or any other typical input/output device.The WTRU 310 may also include memory 319, both volatile and non-volatileas well as interfaces 320 to other WTRUs, such as USB ports, serialports and the like. The receiver 316 and the transmitter 317 are incommunication with the processor 315. The antenna 318 is incommunication with both the receiver 316 and the transmitter 317 tofacilitate the transmission and reception of wireless data. The WTRU 210may also include a power amplifier module 322 that is in communicationwith the processor 315 and transmitter 317 and the receiver 316. Thepower amplifier module 322 may include a single or multiple poweramplifiers. The power amplifier module 322 may alternatively be locatedin the transmitter 317.

In addition to the components that may be found in a typical eNB, theeNB 220 includes a processor 325, a receiver 326, a transmitter 327, andan antenna 328. The receiver 326 and the transmitter 327 are incommunication with the processor 325. The antenna 328 is incommunication with both the receiver 326 and the transmitter 327 tofacilitate the transmission and reception of wireless data. Although asingle antenna 328 is disclosed, the eNB 220 may include multipleantennas.

FIG. 4 shows an overview of carrier aggregation with contiguous carriers400 in accordance with one embodiment. The individual carriers (402,404, 406) may be aggregated to increase available bandwidth. Modulateddata from each carrier (402, 404, 406) may be processed in a single WTRU420 by a discrete Fourier transform (DFT) unit 408, an inverse fastFourier transform (IFFT) unit 410, a digital to analog (D/A) converterunit 412 and a power amplifier (PA) unit 414.

FIG. 5 shows an overview of carrier aggregation with non-continuouscarriers 500 in accordance with another embodiment. As shown in FIG. 5,a first carrier 502 is separated in frequency from a second carrier 504and a third carrier 506. The modulated data from each carrier 502, 504,506 may be processed in a single WTRU 520. The data from the firstcarrier 502 may be processed in a DFT unit 508, an IFFT unit 510, a D/Aunit 512 and PA unit 514. Similarly, the data from the second carrier504 and the third carrier 506 may be processed by a DFT unit 516, anIFFT unit 518, a D/A unit 522, and a PA unit 524. Although shown asseparate units in FIG. 5, each processing unit (508-524) may be combinedinto one or more combined processing units.

In a system using carrier aggregation, a WTRU may use a power controlformula that is based on combined open loop and closed loop powercontrol. In carrier aggregation, radio propagation conditions on eachcomponent carrier (CC) may be different, particularly withnon-contiguous carrier aggregation (CA), as the radio propagationconditions, such as pathloss, for example, may be a function of thecarrier frequency. In addition, interference levels on each CC may bedifferent due to different traffic loads and propagation conditions.Furthermore, one transport block, for example, a hybrid automatedretransmit request (HARQ) process, may be mapped to a single CC whereeach transport block may be processed independently, which implies thatdifferent adaptive modulation control (AMC) sets may be used fordifferent transport blocks.

The WTRU can calculate its transmit power using an open-loop component,a closed loop component, and a band width factor, all indexed to aphysical uplink shared channel (PUSCH) subframe on a particular CC, asfollows:

P _(PUSCH)(i,k)=min{P _(CMAX)(k),10 log₁₀(M _(PUSCH)(i,k))+P _(O) _(_)_(PUSCH)(j,k)+α(j,k)·PL(k)+Δ_(TF)(i,k)+ƒ(i,k)}   (Equation 1),

where P_(PUSCH)(i,k) is the WTRU transmit power, (typically in dBm)indexed to a PUSCH subframe (i) and an uplink (UL) CC(k) and P_(CMAX)(k)is the CC-specific maximum WTRU transmit power on the UL CC(k). Theparameter P_(CMAX)(k) may be configured by the eNB. Alternatively,P_(CMAX)(k) may be equal to P_(CMAX) where P_(CMAX) is the configuredmaximum WTRU transmitted power. For example, if the WTRU can supportonly a single UL CC, then P_(CMAX)(k) may become P_(CMAX). The bandwidthfactor (M_(PUSCH)(i,k)) is the number of allocated physical radiobearers (PRBs) and the open-loop component is P_(O) _(_)_(PUSCH)(j,k)+α(j,k)*PL(k).

The open loop component includes P_(O) _(_) _(PUSCH)(j,k) which is thesum of a cell specific and CC specific nominal component P_(O) _(_)_(NOMINAL) _(_) _(PUSCH)(j,k) and a WTRU specific and possibly CCspecific component P_(O) _(_) _(WTRU) _(_) _(PUSCH)(j,k) respectively.P_(O) _(_) _(NOMINAL) _(_) _(PUSCH)(j,k) and P_(O) _(_) _(WTRU) _(_)_(PUSCH)(j,k) may be signaled to the WTRU. In order to reduce thesignaling overhead, the eNB may provide P_(O) _(_) _(NOMINAL) _(_)_(PUSCH)(j,k) and P_(O) _(_) _(WTRU) _(_) _(PUSCH)(j,k) for a referenceUL CC, such as anchor CC, and provide corresponding offset values forother UL carriers where the individual offset values are relative to thereference UL CC's P_(O) _(_) _(NOMINAL) _(_) _(PUSCH)(j,k) and P_(O)_(_) _(WTRU) _(_) _(PUSCH)(j,k).

The open-loop term α(j,k) is a cell specific and CC specific parameter,where 0≦α(j,k)≦1. The parameter “j” represents an UL transmission model.For example, j=0 for PUSCH transmissions corresponding to asemi-persistent grant, j=1 for PUSCH transmissions corresponding to adynamic scheduled grant, and j=2 for PUSCH transmissions correspondingto the random access response. PL(k) is pathloss estimate for UL CC(k).

The open loop parameters, except for pathloss (PL), may be explicitlysignalled to the WTRU. Some parameters may be CC specific and someparameters maybe CC group specific. The dimensions of a parameter may beCC or CC group specific. A WTRU with a number (L) of aggregated UL CCsmay have a value for each CC, such as P_(O) _(_) _(WTRU) _(_)_(PUSCH)(0), P_(O) _(_) _(WTRU) _(_) _(PUSCH)(1), continuing to P_(O)_(_) _(WTRU) _(_) _(PUSCH)(L−1), for example. Furthermore, rather thansignaling absolute values of a CC specific or CC group specificparameter, a relative (A) value can be used where the relative value maybe relative to a value for a reference UL CC, such as an anchor UL CC,for example. Signaling relative values may reduce signaling overhead.

In the closed-loop component, Δ_(TF)(i,k) is the CC-specific modulationand coding scheme (MCS) offset, and ƒ(i,k) is a closed loop function.Δ_(TF) may be computed by:

Δ_(TF)(i,k)=10 log₁₀((2^(MPR(i,k)·K) ^(s) −1)β_(offset)^(PUSCH)(k))  (Equation 2),

where K_(S)=1.25 and K_(s)=0. K_(s) may be signaled to the WTRU in aparameter, such as the deltaMCS-Enabled parameter, for example.Alternatively, K_(s) may be CC-specific. The termMPR(i,k)=O_(CQI)(i,k)/N_(RE)(i,k) for control data sent via PUSCHwithout the PUSCH data. Otherwise,

${{MPR}\left( {i,k} \right)} = {\sum\limits_{r = 0}^{{C{({i,k})}} - 1}{{K_{r}\left( {i,k} \right)}/{{N_{RE}\left( {i,k} \right)}.}}}$

The term C(i, k) is the number of code blocks in subframe i on UL CC(k),K(i,k) is the size for code block r on UL CC(k), O_(CQI)(i,k) is thenumber of feedback bits on UL CC(k) including cyclic redundancy check(CRC) bits and N_(RE)(i,k) is the number of resource elements on ULCC(k). N_(RE)(i,k) may be determined by N_(RE)(i,k)=M_(sc)^(PUSCH-initial)(i,k)·N_(symb) ^(PUSCH-initial)(i,k). The parameterβ_(offset) ^(PUSCH)(k)=β_(offset) ^(CQI) for control data sent via thePUSCH on UL CC(k) without PUSCH data and 1 (one) otherwise.

The closed loop component for carrier aggregated UL power control may beCC specific. However, for a group of CCs such as contiguous CCs, or CCssharing the same power amplifier, ƒ(i,k) may be common to each CC. Ifaccumulated transmit power control (TPC) commands are used andaccumulation is enabled based on the WTRU specific parameteraccumulation-enabled, then:

ƒ(i,k)=ƒ(i−1,k)+δ_(PUSCH)(i−K _(PUSCH) ,k)  (Equation 3),

where δ_(PUSCH)(i−K_(PUSCH), k) is a WTRU specific accumulation TPCcommand for UL CC(k). The TPC command may be signaled on the physicaldownlink control channel (PDCCH) with a particular downlink controlinformation (DCI) format, such as format 0, 3/3A, or new or extended DCIformat on subframe (i−K_(PUSCH)) where the value of K_(PUSCH) is, forexample, 4 for frequency domain duplex (FDD). For an absolute TPCcommand, if accumulation is not enabled based on the WTRU specificparameter accumulation-enabled, then:

ƒ(i,k)=δ_(PUSCH)(i−K _(PUSCH) ,k)  (Equation 4),

where δ_(PUSCH)(i−K_(PUSCH), k) is a WTRU specific absolute TPC commandfor UL CC(k) that was signaled on the PDCCH with a DCI format such asformat 0, for example, or a new DCI format, on subframe (i−K_(PUSCH)).Alternatively, the TPC command (δ_(PUSCH)) may be defined per group ofCCs such as contiguous CCs or CCs sharing the same power amplifier (PA).For both accumulation and current absolute TPC commands, an initialvalue may be preset. If the P_(O) _(_) _(WTRU) _(_) _(PUSCH)(k) valuefor UL CC(k) is changed by higher layers, then ƒ(i,k)=0. Otherwise,ƒ(0,k)=ΔP_(rampup)+δ_(msg2) where ΔP_(rampup) is provided by higherlayers and δ_(msg2) is the TPC command indicated in the random accessresponse. ΔP_(rampup) and δ_(msg2) may be CC specific. Alternatively, aWTRU may reset accumulation for UL CC when the UL CC becomes activeafter an idle period and the idle period exceeds a predefined expirationtime.

The physical random access channel (PRACH) may be transmitted by theWTRU over different UL CCs. PRACH transmission may also be hopped overdifferent UL CCs. In addition, the accumulation reset of the functionƒ(i,k) may be performed on a CC basis. The function ƒ(i,k) may useaccumulation or current absolute TPC commands, and may be carrierspecific. For instance, the accumulation power adjustment function f(*)may be applied by the WTRU to a first UL CC, while the absolute poweradjustment function f(*) is applied by the WTRU to a second UL CC.However, in order to reduce the relevant parameter signaling overheadand make the power control mechanism simpler, the WTRU specificparameter accumulation-enabled may be common to all the CCs aggregatedfor a given WTRU.

If the WTRU is receiving an accumulated TPC command transmission and theWTRU has reached maximum power, positive TPC commands may not beaccumulated to the respective corresponding accumulation function,ƒ(i,k) for the UL CC receiving a positive TPC command. However, if theWTRU has reached minimum power, negative TPC commands may not beaccumulated to the respective corresponding accumulation function,ƒ(i,k) for UL CCs receiving a negative TPC command.

The power control for PUCCH may be CC specific as follows:

P _(PUCCH)(i,k)=min{P _(CMAX)(k),P _(O) _(_) _(PUCCH)(k)+PL(k)+h(n_(CQI) ,n _(HARQ) ,k)+Δ_(F) _(_) _(PUCCH)(F)+g(i,k)}   (Equation 5),

where P_(PUCCH)(i,k) is the WTRU transmit power, typically in dBm, forPUCCH in subframe i on CC(k) where k is the index of the UL CC. As inEquation 1, P_(CMAX)(k) is the CC-specific maximum WTRU transmit poweron UL CC(k), where P_(CMAX)(k) may be configured by the eNB.Alternatively, P_(CMAX)(k) may be equal to P_(CMAX) where P_(CMAX) isthe configured maximum WTRU transmitted power. For example, if the WTRUcan support only a single UL CC, then P_(CMAX)(k) may become P_(CMAX).P_(O) _(_) _(PUCCH)(k) is a CC specific parameter composed of the sum ofa cell specific and CC specific nominal component P_(O) _(_) _(NOMINAL)_(_) _(PUCCH)(k) and a WTRU specific and possibly CC specific componentP_(O) _(_) _(WTRU) _(_) _(PUCCH)(k) where k represents the UL CC index.P_(O) _(_) _(NOMINAL) _(_) _(PUCCH)(k) and P_(O) _(_) _(WTRU) _(_)_(PUCCH)(k) are provided by higher layers. In order to reduce thesignaling overhead, the eNB may provide P_(O) _(_) _(NOMINAL) _(_)_(PUCCH)(k) and P_(O) _(_) _(WTRU) _(_) _(PUCCH)(k) for a reference ULCC, such as anchor UL CC, and provide corresponding offset values forother UL carriers where the individual offset values are relative to thereference UL CC's P_(O) _(_) _(NOMINAL) _(_) _(PUCCH)(k) and P_(O) _(_)_(WTRU) _(_) _(PUCCH)(k), respectively.

The term h(n_(CQI), n_(HARQ), k) is a PUCCH format dependent value whena PUCCH is transmitted on CC(k). The index of k in h(n_(CQI), n_(HARQ),k) may be dropped, if all PUCCHs are transmitted only on a single UL CC,for example. The parameter Δ_(F) _(_) _(PUCCH)(F) is provided by higherlayers. Each Δ_(F) _(_) _(PUCCH)(F) value corresponds to a PUCCH format(F) relative to another PUCCH format, such as format 1a. The term Δ_(F)_(_) _(PUCCH)(F) may be CC specific. The function g(i, k) is the currentPUCCH power control adjustment function as a function of a WTRU specificand CC specific TPC command δ_(PUCCH)(i, k) as shown in the equation:

$\begin{matrix}{{g\left( {i,k} \right)} = {{g\left( {{i - 1},k} \right)} + {\sum\limits_{m = 0}^{M - 1}\; {{\delta_{PUCCH}\left( {{i - k_{m}},k} \right)}.}}}} & \left( {{Equation}\mspace{14mu} 6} \right)\end{matrix}$

Similar to the power control equation for the PUSCH, the functionδ_(PUCCH)(i,k) for UL CC may be included in a PDCCH with a DCI format,such as format 1a/1B/1D/1/2A/2 or sent jointly coded with other WTRUspecific PUCCH correction values on a PDCCH with a DCI format, such asformat 3/3A, whose CRC parity bits are scrambled with a radio networktemporary identifier (RNTI). The RNTI may be PUCCH specific and TPC orCC specific.

In non-contiguous UL CA, the PUSCH and/or PUCCH transmission may beswitched from one UL CC to another UL CC, for example, due to carrierdependent scheduling and carrier hopping. In this case, the closed looppower control adjustment state function, ƒ(i,k), for PUSCH and g(i, k)for PUCCH on UL CC(k), may not be valid for other UL CCs, becausedifferent CCs may experience different interference conditions andpathloss measurements.

If accumulation is enabled such thatƒ(i,k)=ƒ(i−1,k)+δ_(PUSCH)(i−K_(PUSCH),k), the WTRU may resetaccumulation such that ƒ(i,k)=0 if PUSCH transmission is switched fromone CC to another CC. Similarly, the WTRU may reset accumulation suchthat g(i,k)=0 if PUCCH transmission is switched from one CC to anotherCC.

Alternatively, after the CCs are switched, ƒ(i,k)=ƒ(i−1,k)+Δ_(PL) whereƒ(i−1,k) is the last power control adjustment state used before theswitch. The term Δ_(PL) is the pathloss difference estimate between theCCs before and after the switch.

During a random access procedure, an initial value of ƒ(0,k) may be setto ƒ(0,k)=ΔP_(rampup)+δ_(msg2) until the WTRU gets a value for the P_(O)_(_) _(UE) _(_) _(PUSCH) term from higher layer signaling after a radioresource control (RRC) connection. The functionƒ(0,k)=ΔP_(rampup)+δ_(msg2) can be used, for example, for thetransmission of a random access message in a random access procedurebecause the WTRU may not have established the RRC connection yet. TheWTRU may start the random access attempt in one UL CC, and, afterreceiving a random access response message, switch to another UL CC. TheWTRU may have information regarding the value ofƒ(0,k)=ΔP_(rampup)+δ_(msg2) for the UL CC on which it initiated therandom access and received the message. To determine the power for otherUL CCS, the WTRU can use the same ƒ(0,k)=ΔP_(rampup)+δ_(msg2) valuedetermined for the first UL CC and add an offset to compensate fordifferences between the UL CCs, such as interference. Alternatively, theWTRU can set the ƒ(0,k) to zero (0).

In order to determine a pathloss estimate for an UL CC, pathlossmeasurements may be performed by a WTRU on at least one, and as many asall of the downlink (DL) CCs. A pathloss measurement for each UL CC maybe used. Alternatively, each DL carrier may be mapped to, or paired withan UL carrier for pathloss measurement. The pairings may be configuredon a one-to-one basis or the CCs may be grouped together before pairing.For example, contiguous CCs with the same carrier frequency or within asame frequency/spectrum band may be grouped together. The pathlossmeasurement association and/or configuration that indicates which DL CCsare used for the pathloss estimation for power control of each UL CC maybe configured and signaled to the WTRU in a message from a higher layerentity, such as the RRC. That is, the DL CC used for pathlossestimation/derivation for power control of each UL CC may be configuredper WTRU by the network. Alternatively, the pathloss measurementassociation and/or configuration may be signaled per group of WTRUs orto all the WTRUs within a cell using a system information block (SIB),for example. If the CCs are contiguous, it may not be necessary to carryout pathloss measurements on each contiguous CC, as the pathlossmeasurements may be similar to each other.

An association or mapping rule can be used by the WTRU to associate DLCCs in which pathloss measurements are made with UL CCs on which thepathloss measurements are applied. For example, the WTRU may associatethe pathloss measured on a DL CC with an UL CC that has a similar centeror band frequency.

Alternatively, since pathloss is a function of carrier frequency,pathloss differences between multiple CCs or bands can be calculated asa function of the carrier frequency for a given radio channel condition,radio channel model and/or radio channel environment between a WTRU andan eNB. A WTRU may conduct pathloss measurements on a reference DL CC,such as on an anchor DL CC, for example. The measured pathloss can beapplied by the WTRU to the UL CC associated with a reference DL CC,while pathloss estimates may be made by the WTRU for other UL CCs usingmeasured pathloss levels as follows:

PL(k)=PL_(mes)(k _(f))+Δ_(PL)(k) (dB)  (Equation 7),

where k_(f) is the reference DL CC and PL_(mes)(k_(f)) is the pathlossmeasured on DL CC(k)_(f). The term Δ_(PL)(k) represents the pathlossoffset for UL CC(k) where Δ_(PL)(k) may be determined by the WTRU, forexample, as a function of the center carrier frequencies of thereference CC(k)_(f) and UL CC(k), respectively.

Alternatively, Δ_(PL)(k) may be signaled from the network. Δ_(PL)(k) maybe included in the open loop parameter, P_(O) _(_) _(PUSCH)(j,k) and/orP_(O) _(_) _(PUCCH)(k). More specifically, Δ_(PL)(k) may be included inthe P_(O) _(_) _(NOMINAL) _(_) _(PUSCH)(j,k) term or the P_(O) _(_)_(WTRU) _(_) _(PUSCH)(j,k) term for PUSCH and the P_(O) _(_) _(NOMINAL)_(_) _(PUCCH)(k) term or the P_(O) _(_) _(WTRU) _(_) _(PUCCH)(k) termfor PUCCH by, for example, expanding the current range of P_(O) _(_)_(PUSCH)(j,k), P_(O) _(_) _(NOMINAL) _(_) _(PUSCH)(j,k), P_(O) _(_)_(WTRU) _(_) _(PUSCH)(j,k), P_(O) _(_) _(PUCCH)(k), P_(O) _(_)_(NOMINAL) _(_) _(PUCCH)(k) or P_(O) _(_) _(WTRU) _(_) _(PUCCH)(k).Alternatively, Δ_(PL)(k) may be signaled to the WTRU and a CC specificpower control parameter may be used to signify the term.

Pathloss may be defined as:

PL=(referenceSignalPower)−(higher layer filtered RSRP)  (Equation 8),

where referenceSignalPower is a parameter provided to the WTRU and RSRPis the reference signal received power. An eNB may allocate differentcell-specific reference signal (CRS) transmit power levels on differentDL CCs for purposes such as traffic load control or interferencemanagement, for example. The individual reference transmit power may besignaled to the WTRU. Alternatively, in order to reduce signalingoverhead, the eNB may provide the CRS transmit power for a reference DLCC, such as anchor CC, and provide relative CRS power offsets for otherDL CCs where the CRS power offsets are relative to the reference DL CCCRS power. Rather than separately signaling the CRS power offsets, theindividual CC power offsets may be included in corresponding P_(O) _(_)_(PUSCH)(j,k) for PUSCH or P_(O) _(_) _(PUCCH)(k) for PUCCH. Morespecifically, the CRS power offsets may be included in the P_(O) _(_)_(NOMINAL) _(_) _(PUSCH)(j,k) term or the P_(O) _(_) _(NOMINAL) _(_)_(PUCCH)(k) term.

One DL reference CC may provide the CRS to derive the pathloss. The WTRUmay make the pathloss measurement based on the CRS and then makecorrections based on frequency differences between each UL carrier andthe frequency of the DL reference CC. The network may assign a DLcarrier to be used as the DL reference. This method may be suitable forcontiguous UL transmissions and noncontiguous transmissions, providedaccurate corrections can be derived or determined.

Multiple DL reference CCs may be used. The DL reference CCs may beconfigured by the eNB. The WTRU may make measurements on the referenceCCs and follow an algorithm to map these measurements into an open loopestimate for each of the UL CCs. If appropriate, the WTRU may makefrequency-dependent corrections. This may be most suitable fornoncontiguous operation where it may be necessary to deal withsignificant separation of the UL CCs. It also may provide sufficientperformance benefit to also apply to contiguous operation.

The network may select a single CC for the reference signal based on theCC that provides the most representative frequency. For example, the DLCC that has the least frequency separation from the UL CC may be usedfor uplink power control, the anchor carrier may be used or the DL CCthat has the largest pathloss may be used.

Alternatively, a combination of the measured pathloss of more than oneDL CC can be used for UL power control. Criteria for selecting the CCsto be used may include choosing the CCs with a frequency that isseparated from the uplink carrier frequency by less than a particularthreshold. The threshold may be preconfigured or may be derived by theWTRU. Other criteria that may be used to select the CCs may includeexcluding CC carriers that are non-contiguously aggregated with the DLcarrier and have the smallest frequency separation from the UL CC. Thecombination of CCs may be a linear combination or a weighted average ofcombined CCs.

If the frequency separation between DL and UL CCs is more than apredetermined threshold, a correction term for pathloss may be appliedby the WTRU. Alternatively a correction term for pathloss for UL powercontrol may be applied regardless of the threshold being exceeded.Precise pathloss may be required due to several factors, such as theradio channel conditions, for example.

Measured pathloss estimates can be combined by the WTRU using anaveraging or filtering technique. Weights can be assigned to differentmeasurements. For example, the pathloss of the DL CC which has thesmallest frequency separation from the UL CC might have a relativelylarger weight. The weight might be configured by the eNB and signaled tothe WTRU.

When there are multiple DL CCs available for pathloss measurement, theeNB may use different CRS transmit powers on the DL CCs. The individualCRS transmit powers may be transmitted to the WTRU by higher layersignaling. Alternatively, the eNB may provide the CRS transmit power fora reference DL CC, such as an anchor CC, for example, and relative CRStransmit powers or power offsets for other DL CCs where the relative CRStransmit powers are relative to the reference DL CC's CRS transmitpower. The WTRU may perform the RSRP measurement on the reference DL CCand calculate the PL on other DL CC, for example, DL CC(n) as:

PL(n)=(referenceSignalPower)−(higher layer filtered RSRP)+P_(offset)(n)  (Equation 9),

where P_(offset)(n) is the relative CRC power or power offset for DL(n).

Aggregated UL carriers may experience disparate pathloss metrics. Forexample, pathloss is a function of carrier frequency and the type ofcell deployment. A WTRU in a macro cell may experience a differentpathloss than in a micro cell. The pathloss of an UL CC can be measuredby the WTRU and the other pathloss of other CCs can be computed from themeasurement.

In order to determine pathloss, the WTRU may choose an UL CC as areference CC. The reference CC may be the one with the lowest carrierfrequency, the highest carrier frequency or middle carrier frequency.Alternatively, the eNB may signal the WTRU which UL CC the WTRU shouldconsider as reference CC.

The WTRU measures the pathloss in a DL CC. The resulting pathloss may beused for the transmit power setting for the UL reference CC. For otherUL CCs, the WTRU calculates the relative pathloss, that is, the pathlossoffset, between the reference UL CC and other UL CCs according to thepathloss formula on each CC, and applies the pathloss offset for theother CC.

Due to potentially different propagation law or environments, thepathloss formula on each CC might be different. Therefore, for twonon-contiguous CCs, a reference CC and a CC(i), with carrier frequencyƒ_(ref) and ƒ_(i) respectively, the pathloss formulas are:

PL_(ref) =C _(ref)+10n _(ref) log 10(D)+10m _(ref) log10(ƒ_(ref))  (Equation 10),

and

PL_(i) =C _(i)+10n _(i) log 10(D)+10m _(i) log 10(ƒ_(i))   (Equation11),

where D is the distance from transmitter to receiver. The relativepathloss, Δ_(PL) between the reference CC and other CC can be derivedas:

Δ_(PL)(i)=C _(ref) −C _(i)+10(n _(ref) −n _(i))log 10(D)+10m _(ref) log10(ƒ_(ref))−10m _(i) log 10(ƒ_(i))   (Equation 12)

A correction term may be applied to the pathloss offset calculation toaccount for different channel models in Equation 11, as follows:

Δ_(PL)(i)=C _(ref) −C _(i)+(n _(ref) −n _(i))log 10(D)+10m _(ref) log10(ƒ_(ref))−10m _(i) log 10(ƒ_(i))+corr_term   (Equation 13),

where corr_term is the correction term for pathloss offset. The termcorr_term may be configured or signaled by network. The values ofcorr_term can be in the form of lookup table.

For example, where two CCs follow the same pathloss, for a particularchannel model, the pathloss may be calculated as PL=58.83+37.6 log10(D)+21 log 10(ƒ_(c)), where D is the distance from transmitter toreceiver and ƒ_(c) is the reference CC frequency. Then the relativepathloss, Δ_(PL) between the reference CC and other CCs is:

${\Delta_{PL}(i)} = {{{21\log \; 10\left( f_{c} \right)} - {21\log \; 10\left( f_{o} \right)}} = {{21\log \; 10\left( \frac{f_{c}}{f_{o}} \right)} + {corr\_ term}}}$

where ƒ_(o) is the other carrier frequency.

The radio channel propagation model may be known to the network. Ratherthan use a fixed propagation exponent, such as 21, the value may be acell-specific parameter signaled by the network. For example, theexponent may take the values such as 21, 30, 35, 40, for example, using2 signaling bits.

Alternatively, the eNB may transmit the pathloss offsets for the otherUL CCs to the WTRU. The eNB can determine the offsets based on ameasurement of uplink sound reference signals (SRS) on different UL CCs.The CC specific offset may be included in the open loop parameter, P_(o)_(_) _(PUSCH) for PUSCH and P_(o) _(_) _(PUCCH) for PUCCH. Inparticular, as channel conditions may be different for different WTRUs,the CC specific offset may be included in the WTRU specific componentP_(o) _(_) _(WTRU) _(_) _(PUSCH) for PUSCH and P_(o) _(_) _(WTRU) _(_)_(PUCCH) for PUCCH. Alternatively, the eNB may base the offsets on ameasurement of a reference signal. The eNB may inform the WTRU about therecommended correction term for each of the uplink CCs.

FIG. 6 is a signal diagram for a method of power control 600 inaccordance with an embodiment. At 602, the eNB 620 signals a pathlossmeasurement, such as DL CRS, and pathloss setting rules to the WTRU 630.The pathloss setting rules may include, for example, the UL referenceCC, DL reference CC, UL/DL CC pairing information, and pathloss offsetbetween CCs, if any.

At 604, the WTRU 630 performs pathloss measurements on aggregated CCsaccording to the pathloss measurement and setting rules. At 606, theWTRU 630 uses measured pathloss to set transmit power for uplinktransmission on aggregated CCs, and calculates power headroom foraggregated CCs. At 608, the WTRU 630 transmits UL signals to the eNB 620using the calculated power settings.

As shown in Equation (1) and (5), respectively, separate TPC commandsmay be used for PUSCH and PUCCH, respectively. For example, separate TPCcommands may be transmitted from the eNB to the WTRU for PUSCH and PUCCHpower control, respectively. For PUSCH power control, the TPC commandmay be defined per UL CC and per WTRU. For PUCCH power control, the TPCcommand may be defined per UL CC and per WTRU. If the WTRU istransmitting multiple PUCCHs on a UL CC, separate TPC commands for theindividual PUCCHs may be received by the WTRU. Upon receiving the TPCcommands, the WTRU may apply each of them for the associated PUCCH.

Alternatively, the TPC command for PUSCH or PUCCH may be defined pergroup of UL CCs or for all UL CCs. The eNB may configure the WTRUthrough higher layer signaling to inform the WTRU whether the TPCcommand is defined per CC, per group of CCs, or all CCs. For example, aTPC command may be configured to control a group of UL CCs where the CCsare transmitted using the same PA.

TPC commands for the PUSCH in a carrier aggregated system may bereceived by the WTRU in the PDCCH with a particular DCI format, such asDCI format 0 or DCI format 3/3A. The DCI format may include PUSCH powercontrol for a carrier aggregated system. Similarly, TPC commands for thePUCCH can be received in the WTRU with a particular format such as DCIformat 1A/1B/1D/1/2A/2 or DCI format 3/3A, where the respective formatmay facilitate PUCCH power control in a carrier aggregated system.

Each unit of control data may have a CRC. The CRC may be scrambled withan radio network temporary identifier (RNTI). The RNTI may be WTRUspecific, group specific, or function specific, for example, TPC. EachWTRU looks for the RNTIs that would indicate that there is controlinformation for that WTRU. The WTRU may look for an RNTI that is WTRUspecific, CC specific, PUSCH specific, TPC specific, PUCCH specific orany combination of WTRU, CC, PUSCH, PUCCH and TPC.

A PDCCH carrying a CC-specific TPC command may have an RNTI where CRCbits of the PDCCH are scrambled with the RNTI. The RNTI may be ULCC-specific. For example, a PDCCH with DCI format 0 or DCI format1A/1B/1/2A/2, for example, may have the C-RNTI, SPS-CRNTI or ULCC-specific C-RNTI of the WTRU. A PDCCH with DCI format 3/3A for PUSCHmay have the TPC-PUSCH-RNTI or UL CC-specific TPC-PUSCH-RNTI of the WTRUand a PDCCH with DCI format 3/3A for PUCCH may have the TPC-PUCCH-RNTIor UL CC-specific TPC-PUCCH-RNTI of the WTRU.

The WTRU can receive multiple DCI formats including, for example, DCIformat 0/1/2/3/3A, in the same subframe. As the TPC command is carriedin the PDCCH, the TPC command signaling method may depend on the PDCCHstructure. For example, when TPC commands for a WTRU are included in aPDCCH with a DCI format such as DCI format 3/3A, the TPC command may bejointly coded with other TPC commands for other WTRUs and other CCs.

When a TPC command for PUSCH is included in the PDCCH with a particularDCI format, such as DCI format 0, and the TPC command is in an UL grant,the TPC command may be applied by the WTRU to a particular UL CC. TheTPC command in an UL grant for a given WTRU may be associated with an ULCC. The WTRU may receive information about the associated UL CC from theeNB or it may determine the association using a preconfigured mapping orrule. For example, a TPC command in the PDCCH with an UL grant may beapplied by the WTRU to the UL CC for which the UL grant applies.

The association of the PDCCH with an UL grant and UL CC can betransmitted to the WTRU by use of an indicator such as a layer one (L1)explicit indicator, an implicit UL CC indicator or in RRC signaling, forexample. If an explicit L1 CC indicator in the PDCCH is used so that theWTRU knows which TPC commands applies to each UL CC, then the structureof the DCI format may accommodate the L1 CC indicator. For an implicitCC indicator, a WTRU's UL CC-specific C-RNTI can be used such that for aUL CC, the corresponding WTRU's UL CC-specific C-RNTI is scrambled withCRC bits of the PDCCH.

Alternatively, at least a group of TPC commands, and as many as all TPCcommands for the PUSCH may be carried in a single UL grant. An index fora TPC command to UL CC mapping can be used so that the WTRU knows whichTPC bits apply to each UL CC. Alternatively, an association of TPCcommands and UL CC identification or index may be established throughhigher layer signaling or may follow one or more rules implemented inthe WTRU. Accordingly, the WTRU may use preconfigured rules to determinewhich commands corresponds to each UL CC.

When a TPC command for the PUSCH is included in a first PDCCH with aparticular format, such as DCI format 3/3A for example, a CC specific orCC group specific TPC command for a given WTRU may be jointly coded withother CC specific or CC group specific TPC commands for other WTRUs. TheCRC parity bits may be scrambled with a TPC-PUSCH-RNTI or aCC-TPC-PUSCH-RNTI. The CC-TPC-PUSCH-RNTI may be a UL CC-specificTPC-PUSCH-RNTI. Another CC-specific TPC command for the WTRU may betransmitted on another associated PDCCH using a CC-TPC-PUSCH-RNTI thatis different than the one used in the first PDCCH. For example, the TPCcommand for a first UL CC of a first WTRU may be jointly coded with thefirst UL CC TPC commands for a second and a third WTRU. The TPC commandsmay be transmitted in the PDCCH with a particular DCI format, such asformat 3/3A, for example. The first, second and third WTRUs may have thesame TPC-USCH-RNTI or k-th CC-TPC-PUSCH-RNTI. If the first WTRU hasanother active UL CC, for example, a second CC, then the correspondingTPC command may be jointly coded with the second UL CC TPC commands forother WTRUs. The TPC commands for each WTRU may be coded using differentTPC-PUSCH-RNTIs or CC-TPC-PUSCH-RNTIs. Each location of the CC-specificTPC bits for each WTRU within the PDCCH may be signaled to the WTRU viahigher layer signaling. While this example includes three WTRUs, thenumber of WTRUs is for example only, any number of WTRUs may use themethod disclosed herein.

The WTRU may receive information such as the TPC parameter and the TPCindex. For example, the TPC parameter may indicate how to allocate TPCbits to each WTRU and each CC. The TPC index may be CC-specific per WTRUor common to all CCs per WTRU.

Alternatively, all the CC-specific TPC commands for all active UL CCsfor a first WTRU may be jointly coded with CC-specific TPC commands fora second and a third WTRU in a PDCCH with a particular DCI format, suchas DCI format 3/3A or extended DCI format 3/3A, for example. The CRCparity bits may be scrambled with a TPC-PUSCH-RNTI. Each location of therespective CC-specific TPC command bits for the first WTRU may besignaled to the WTRU via higher layer signaling. Included in thelocation information may be the TPC parameter and the TPC index. TheTPC-index may be defined for each WTRU. The information regarding whichTPC bit corresponds to which CC may be signaled to the WTRU explicitlyby higher layers. Alternatively, the WTRU may determine thecorrespondence implicitly by using a preconfigured rule or mapping. Withthe implicit signalling, the CC specific TPC bits for a WTRU may beplaced in ascending order with the UL CC index and the WTRU may receiveinformation as to where to starting reading the TPC bits within thePDCCH it receives from the eNB using, for example, higher layersignalling.

For CC-specific or CC group-specific TPC command transmission for PUSCH,the WTRU may attempt to decode a PDCCH of a first DCI format, such asDCI format 0, for each UL CC on the associated DL CC using anidentifier, such as a WTRU's C-RNTI, a WTRU's CC specific C-RNTI, an SPSC-RNTI, or a CC specific SPS C-RNTI, for example, in every subframeexcept when the WTRU is in DRX mode or in a measurement gap. At the sametime, the WTRU may also attempt to decode a PDCCH of a second DCIformat, such as DCI format 3/3A, for each UL CC, using a differentidentifier such as TPC-PUSCH-RNTI or CC-TPC-PUSCH-RNTI, in everysubframe except when in the WTRU is in DRX mode or in a measurement gap.If accumulation TPC commands for the UL CC(k) are transmitted, theclosed loop PC adjustment function, ƒ(i,k) may be equal to ƒ(i−1,k)+δ_(PUSCH)(i−K_(PUSCH), k) where δ_(PUSCH)(i−K_(PUSCH), k)=0 dB forthe (i−K_(PUSCH))^(th) subframe where no TPC command is decoded, wherethe WTRU is in DRX mode or where a measurement gap occurs on theassociated DL CC. If absolute TPC commands for the UL CC(k) aretransmitted, ƒ(i,k)=δ_(PUSCH)/(i−K_(PUSCH), k). The function ƒ(i,k)=ƒ(i−1, k) for a subframe where no TPC command is decoded for the ULCC, where the WTRU is in DRX mode, or where a measurement gap occurs onthe associated DL CC. This may also occur if CC group specific TPCcommands are transmitted. For a given UL CC, if a first DCI format, suchas DCI format 0 and a second DCI format, such as DCI format 3/3A areboth detected in the same subframe, the WTRU may use the TPC command,δ_(PUSCH)(i, k), provided in the first DCI format.

When a TPC command for PUCCH is included in PDCCH with a DCI format suchas DCI format 1A/1B/1D/1/2A/2, for example, the DL grant and schedulinginformation may be included in the PDCCH as well. The TPC command may beapplied by the appropriate WTRU to control PUCCH transmit power on aparticular UL CC. The TPC command may be applied to the UL CC associatedwith each DL grant or each bit of scheduling information for a givenWTRU. The WTRU may receive information about the associated UL CC fromthe eNB or it may determine the association using a preconfiguredmapping or rule. For example, a TPC command carried in the PDCCH with DLgrant or scheduling information and using a particular DCI format, suchas DCI format 1A/1B/1D/1/2A/2, for example, may be applied to an UL CCon which an ACK/NACK is transmitted. The ACK/NACK may be associated withthe DL grant and scheduling information in the PDCCH. The association ofthe PDCCH with the DL grant and UL CC can be given to the WTRU by using,for example, an explicit L1 CC indicator within the PDCCH, an implicitUL CC indicator or by RRC signaling.

If an explicit L1 CC indicator is used within the PDCCH, the WTRU mayknow which TPC commands apply to each UL CC. The structure of the DCIformat may accommodate the L1 CC indicator.

If an implicit UL CC indicator is used, the WTRU's UL CC-specific C-RNTIcan be used such that, for an UL CC, the corresponding WTRU's ULCC-specific C-RNTI may be scrambled with CRC bits of the PDCCH.Alternatively, at least a subset, and as many as all, the TPC commandsfor PUCCH may be carried in a DL grant or scheduling informationmessage. An index for a TPC command to UL CC mapping can be used so thatthe WTRU knows which TPC bits apply to each UL CC. Alternatively, anassociation of TPC commands and UL CC identification may be establishedthrough higher layer signaling or may follow one or more rulesimplemented in the WTRU. The WTRU may use preconfigured rules todetermine which commands corresponds to each UL CC.

At least a group, or as many as all TPC commands for a given PUCCH for agiven WTRU may be bundled together. The resulting bundle of TPC commandsmay be carried in a PDCCH such as a DL reference CC. The bundle may alsobe carried in multiple PDCCHs with a particular DCI format, such as DCIformat 1A/1B/1D/1/2A/2 or DCI format 3/3A. The TPC command may beapplied to a group, or as many as all UL CCs.

Alternatively, δ_(PUCCH) may be WTRU specific, but not CC specific whenit is signalled on a PDCCH. The term δ_(PUCCH) may be carried on a DLreference CC where a single δ_(PUCCH) value controls the PUCCH power.Table 1 shows examples of TPC signaling in an UL grant.

TABLE 1 TPC SIGNALING One UL GRANT per UL One UL GRANT One UL GRANT pergroup of carrier for all UL carriers UL carriers One TPC per Separate orjoint TPC Joint TPC Group or joint TPC signaling. UL carrier signalingcan be applied. signaling is For group TPC signaling, For separate TPCsignaling, applied and there several TPC commands for UL the UL GRANTcarrying TPC is one UL GRANT carriers scheduled by the same is decodedby the WTRU in carrying TPC. PDCCH are signaled on each predetermined DLcarriers, or This UL GRANT UL scheduling grant. assigned DL carriersthat are WTRU is decoded For joint TPC signaling, the signaled, orconfigured DL by the WTRU to index of UL GRANT carrying carriers byblind decoding all obtain the TPC. TPC is known by the carriers.Preconfigured DL carrier For joint TPC signaling, the index (thatcarries the single index of the UL GRANT TPC) carrying TPC is known bythe Assigned DL carrier index that WTRU from the preconfigured issignaled, DL carrier index (that carries Different UL scheduling grantthe single TPC), or assigned format (other than those does DL carrierindex that is not carry TPC) signaled, or different UL scheduling grantformat (one not carrying TPC) One TPC per Separate or joint TPC JointTPC Group or joint TPC signaling. a subset or signaling. For bothmethods, signaling is For group TPC signaling, group of UL the index ofthe UL GRANT applied and there several TPC commands for UL carrierscarrying TPC is known by the is one UL GRANT carriers scheduled by thesame WTRU from the preconfigured carrying TPC. PDCCH are signaled oneach DL carrier index (that carries This UL GRANT UL scheduling grant.the single TPC), or the WTRU is decoded For joint TPC signaling, theassigned DL carrier index that by the WTRU to index of UL GRANT carryingis signaled, or a different UL obtain the TPC. TPC is known byscheduling grant format (one Preconfigured DL carrier not carrying TPC)index (that carries the single TPC) Assigned DL carrier index that issignaled, Different UL scheduling grant format (other than those doesnot carry TPC) One TPC for The only TPC command is The only TPC The onlyTPC command is all UL carried in one UL GRANT, command is carried in oneUL GRANT, carriers whose index is known by the carried on the only whoseindex is known WTRU from the preconfigured UL GRANT. This PreconfiguredDL carrier DL carrier index (that carries UL GRANT index (that carriesthe single the single TPC), or an WTRU is decoded TPC) assigned DLcarrier index that by the WTRU to Assigned DL carrier index that issignaled, or a different UL obtain the TPC. is signaled, schedulinggrant format (one Different UL scheduling grant not carrying TPC) format(other than those does not carry TPC)

FIG. 7 is a signal diagram showing a power control method 700 inaccordance with another embodiment. At 702 the eNB 720 signals the TPCto the WTRU 730 in accordance with the methods described herein. The TPCis transmitted in an UL grant with DCI format 0. At 704, upon receivingthe UL grant and the TPC from the network, the WTRU 730 determines theassociation between the TPC and its corresponding carriers according tothe appropriate rule taken from Table 1, or as otherwise describedherein. At 706 the WTRU applies the received TPC to set transmit powerfor uplink transmission on aggregated carriers accordingly. At 708, theWTRU 730 transmits an uplink signal with the received TPC applied.

Rather than being be CC specific, a TPC command may be defined for agroup of UL CCs or for all UL CCs. The eNB may configure the WTRUthrough, for example, higher layer signalling, so that the WTRU mayrecognize whether the TPC command is defined per CC, per group of CCs,or for the entire UL. For example, a TPC command may be configured tocontrol a group of UL CCs where the CCs are transmitted using the samePA in the WTRU. Contiguous CCs may share the same PA at the WTRU. TheWTRU and the eNB may exchange configuration information regarding howthe WTRU associates CCs with each PA. The exchange of configurationinformation may be done via higher layer signalling. If TPC transmissionis per CC or per group of CCs, an association or mapping between the TPCcommand and the applied UL CCs may be preconfigured and provided to theWTRU via, for example, higher layer signalling.

A single TPC command may be used for PUCCH power control per CC. The TPCcommand may be transmitted on an associated DL CC, and the parameters h(n_(CQI), n_(CQI),k) and Δ_(F) _(_) _(PUCCH)(F), may be applied perPUCCH.

Multiple PUCCHs may be simultaneously transmitted from a WTRU on a CC ormultiple CCs. For example, a WTRU may transmit one or moreacknowledge/non-acknowledge (ACK/NACK) signals in a first PUCCH andother feedback, such as a channel quality indicator (CQI) or a precodingmatrix indicator (PMI) in a second PUCCH on the same CC in a subframe.The power settings for each respective PUCCH may be implementedseparately, using Equation 5. If more than one PUCCH are simultaneouslytransmitted from a WTRU on a UL CC, then separate TPC commands for theindividual PUCCHs may be received by the WTRU. Upon receiving the TPCcommands, the WTRU may apply each of the TPC commands to the associatedPUCCH. Alternatively, the WTRU may combine all the TPC commands into asingle TPC command and apply the TPC command for all the PUCCHs on theUL CC. For example, the TPC commands may be treated as identical. Oncethe WTRU successfully decodes the TPC command in one of thecorresponding PDCCHs in a subframe, it applies the TPC command for allthe PUCCHs and may not decode the other TPC commands in the subframe.

If more than one channel is being transmitted simultaneously, thechannels may use the same TPC commands. For example, the TPC commandsfor the PUSCH may be used by the WTRU for the PUCCH. In this case, theeNB will not send the TPC commands for PUCCH and the closed loopcomponent for PUCCH, as shown above in Equation 1, but may rely on theTPC commands for PUSCH instead. The accumulate TPC commands for PUSCHmay be used by the WTRU.

Alternatively, if more than one channel is simultaneously transmitted,the TPC commands may be combined by the WTRU. For example, the TPCcommands for PUSCH and PUCCH, respectively, may be combined and thecombined TPC command may be applied by the WTRU to both the PUSCH andthe PUCCH. The accumulation TPC commands for PUSCH may be used.

The PUSCH and the PUCCH may be transmitted on a single UL CC.Furthermore, multiple PUCCHs, if necessary, may be simultaneouslytransmitted on a UL CC. Power control for the simultaneously transmittedPUCCH and PUSCH may be implemented per physical channel and/or per CC,using Equation 1 and Equation 5, respectively. If the sum of therequired transmit power for the PUSCH and the PUCCH on UL CC(k) exceedsP_(CMAX)(k) where P_(CMAX)(k) is the CC-specific configured maximum WTRUtransmit power for UL CC(k), the WTRU may need to back off the totaltransmit power to P_(CMAX)(k). The CC-specific maximum transmit power,P_(CMAX)(k), may be signaled by the eNB via higher layer signaling.

The power control scheme for multiple CCs may depend on the WTRU's radiofrequency (RF)/transceiver architecture. In particular, the scheme maydepend on the number of PAs in the WTRU. Contiguous CCs may use the samePA, while non-contiguous CCs may use separate PAs. If multiple UL CCsare transmitted, the sum of the powers on the individual UL CCs may notexceed a configured total maximum WTRU transmit power, P_(CMAX), whereP_(CMAX) may depend on the WTRU power class, allowed tolerances andadjustments, and a maximum allowed transmit power signaled to the WTRUby the eNB. The value of P_(CMAX) may be provided by the eNB via higherlayers.

P_(CMAX) may be less than or equal to the sum of the CC-specific maximumtransmit powers, P_(CMAX)(k), on all the active UL CCs. When the WTRU isequipped with multiple PAs, for example, for multiple non-contiguous CCsin different frequency bands, Pcmax may be equally distributed among allthe PAs such that P_(CMAX) _(_) _(PA) _(_) _(i)=P_(CMAX)−10*log 10(N)(dBm) where P_(CMAX) _(_) _(PA) _(_) _(i) is the maximum transmit powersupported by the individual PA and N is the number of PAs at the WTRUdevice. Alternatively, P_(CMAX) _(_) _(PA) _(_) _(i) may be differentfor different PAs. If the total required WTRU transmit power exceedsP_(CMAX), the WTRU may need to back off the transmit power to reduce itin order to not exceed P_(CMAX). If the required power for a specific PAexceeds the PA maximum allowed power, P_(CMAX) _(_) _(PA) _(_) _(i), theWTRU may need to reduce the transmit power in order to not exceedP_(CMAX) _(_) _(PA) _(_) _(i).

In addition to UL carrier aggregation, for WTRUs supporting UL MIMO,each antenna may be connected to a PA and each PA may have a differentmaximum transmit power requirement. The WTRU transmit power for eachphysical channel may be distributed over the transmit antennas. When thetotal required transmit power on each antenna exceeds the maximum PApower, the WTRU may need to adjust the transmit power to avoid exceedingthe limit.

A WTRU may be limited by multiple levels of maximum power transmission.The WTRU may have a total transmission power limitation. Each CC mayhave a power limit. Each PA may have a power limit. Each transmissionchannel may have a power limit. Therefore, a WTRU must contend withmultiple limitations of the WTRU's transmit power.

The maximum transmit power of a WTRU may be limited by the WTRU's powerclass definition, a higher layer configuration or by the WTRU's PAs. TheWTRU transmit (TX) power may be subject to maximum power limitations.For example, the total WTRU power on a individual UL CC(k) may besubject to a CC-specific maximum TX power P_(CMAX)(k). The sum of theWTRU TX power on all active CCs may be subject to a total maximum TXpower P_(CMAX). The total TX power on each CC group(m) may be subject toa maximum CC group TX power, denoted by P_(CMAX) _(_) _(CC) _(_)_(group)(m), where the CC(m) consists of a subset of UL CCs and

${P_{{{CMAX}\_ {CC}}{\_ {gr}}\mspace{11mu} {oup}}(m)} < {\sum\limits_{k \in {{{CC}\_ {group}}{(m)}}}{{P_{CMAX}(k)}.}}$

For example, a CC group may consist of contiguous UL CCs sharing thei^(th) PA in the WTRU. In this case, P_(CMAX CC) _(_) _(group)(m) may beequal to the maximum PA power, P_(CMAX PA) _(_) _(i). If any combinationof the above maximum power limitations occurs in a subframe transmittedby the WTRU, the WTRU may need to reduce or scale the transmit powerproperly, in order to not violate the power limitations.

When a WTRU is transmitting using multiple CCs and simultaneous PUSCHand PUCCH transmission, the transmit power of the PUSCH and/or the PUCCHon each CC may be computed independently per physical channel per CC.The WTRU may use Equation 1 for PUSCH and Equation 5 for PUCCH. In asubframe, if the sum of all the power levels on all the CCs exceeds thetotal maximum WTRU power, P_(CMAX), and/or the total transmit power onan UL CC(k) exceeds the CC-specific maximum power, P_(CMAX)(k), the WTRUmay reduce or scale some or all of the transmit power levels properly.For example, if the total transmit power on UL CC(k) exceedsP_(CMAX)(k), then the WTRU initially may reduce the total power on thatUL CC(k) to P_(CMAX)(k). If the sum of all the transmit power levels onall the UL CCs exceeds the total maximum WTRU power, P_(CMAX), the WTRUmay reduce the total power over all the CCs to P_(CMAX).

Power reduction may be based on a priority of the CCs and the channelson each CC. The priority may be determined based on requirements forcontrol and data transmission and/or quality of service (QoS) of data.In one example, the PUCCH may be prioritized over PUSCH, particularlywhen the PUSCH does not include UL control information (UCI). PUSCH withUCI may have priority over a PUSCH without UCI. Similarly, a UL CCcarrying the PUCCH or PUSCH with UCI may have priority over other UL CCcarrying a PUSCH without UCI. The WTRU may prioritize UL CCs and thenprioritize channels on the prioritized individual UL CC. Some UL CCs orchannels may be dropped and the transmit power of the channel scaled orset to zero, if necessary.

The channel priority and/or CC priority may be predefined and signaledto the WTRU through higher layers. Alternatively, the WTRU mayautonomously determine the priority and the eNB may do blind detectionon the transmitted physical channels with priority.

When an UL CC(k) includes a simultaneous PUSCH/PUCCH transmission andthe sum of the powers of the PUSCH and all the PUCCHs exceedsP_(CMAX)(k), the WTRU may reduce the power of some of the channels basedon channel priority. For example, the PUCCH may have priority over thePUSCH and the power of the PUSCH may be reduced without the PUCCH powerbeing affected. The PUSCH may be dropped, if the reduced power of thePUSCH is less than a predefined threshold or a minimum transmit power.Furthermore, if there is a need to further reduce the power of otherchannels, such as other PUCCHs, the WTRU may reduce the power of some ofPUCCHs with next lowest priority to remain within the maximum transmitpower limitation (P_(CMAX)(k)).

FIG. 8 is a flow chart showing a power control method 800 in accordancewith an alternative embodiment. At 802, the WTRU may calculate the powerof a PUCCH or PUSCH with a highest priority. At 804, the resulting powerlevel, P_(1st) _(_) _(priority), may be compared to a maximum powerlevel. If the P_(1st) _(_) _(priority) is equal to or greater than themaximum WTRU power, Pcmax, or maximum WTRU PA power, Pcmax_i, then, at806, all other physical channels may be dropped. At 808, the PUCCH orPUSCH with highest priority may be transmitted at the maximum power.Otherwise, at 806, the WTRU determines if the channel currently beingconfigured is the last channel. If not, at 810, the WTRU calculates thepower of a PUCCH or PUSCH with next priority, using, for example, a CQIvalue. At 812, the calculated power level, P_(2nd) _(_) _(priority), iscompared to the available WTRU power. If P_(2nd) _(_) _(priority) isequal to or greater than the available WTRU power (i.e., Pcmax−P_(1st)_(_) _(priority)), then, at 814, the WTRU transmits only the first twopriority physical channels where the first priority physical channel istransmitted at the calculated transmit power, P_(1st) _(_) _(priority),and the second priority physical channel is transmitted at the remainingWTRU power. Otherwise (P_(2nd) _(_) _(priority)<Pcmax−P_(1st) _(_)_(priority)), at 816, all of P_(2nd) _(_) _(priority) is used for thesecond priority channel. The procedure then returns to 805 and may berepeated with the remaining physical channels, if any, with priority, aslong as the remaining WTRU transmit power is not less than or equal tozero or a minimum transmit power level.

If, however, at 805, the WTRU determines that it is configuring the lastchannel, the WTRU transmits all channels at their determined powerlevels and ends the procedure.

When one CC includes a simultaneous PUSCH/PUCCH transmission and thetotal power of the PUSCH in a subframe exceeds P_(CMAX), the power perradio bearer (RB) may be reduced by the same amount such that thereduced total power is equal to P_(CMAX). Alternatively, for asimultaneous PUSCH/PUCCH transmission, if the sum of the powers of PUSCHand PUCCH exceeds P_(CMAX), a proper power adjustment method may beperformed to maintain the maximum transmit power limitation. WTRU powermay be allocated based on priority where the priority is determined bycontrol information and data in the subframe.

FIG. 9 is a flow diagram of a method of power control 900 in accordancewith another alternative embodiment. In another embodiment, at 902, theWTRU calculates the transmit power of the PUCCH. If multiple PUCCHsoccurs in the subframe, calculate the transmit power of each PUCCH withpriority. At 904, the WTRU determines if there is sufficient poweravailable for the PUCCH transmission. If there is available power forPUCCH transmission, at 906 the remainder of any power is allocated tothe PUSCH transmission. Otherwise, at 908, the WTRU drops the PUSCHtransmission.

FIG. 10 is a flow diagram of a method of power control 1000 inaccordance with yet another alternative embodiment. At 1002, the WTRUcalculates the transmit power levels of the individual physicalchannels. At 1004, the WTRU sums the power levels. At 1006, the WTRUcompares the sum of all the power levels to the maximum allowable power.If the sum of all the power levels exceeds the maximum transmit power,at 1008 the power levels of each channel are backed off. Otherwise, at1010, the channels are transmitted.

When the PUSCH and PUCCH are simultaneously transmitted on an UL CC andthe sum of the power levels exceeds the maximum transmit power, thepower density, that is, the power per subcarrier, may be reduced by thesame amount such that the reduced total power is equal to the maximumpower.

Alternatively, for a simultaneous PUSCH/PUCCH transmission, if the sumof the powers of the PUSCH and the PUCCH exceeds a maximum power, aproper power adjustment method may be performed to maintain the maximumtransmit power limitation. WTRU transmit power may be allocated based onpriority.

The sum of all the power levels on all the CCs may exceed a maximum WTRUallowed transmit power, such as the maximum WTRU transmit power, Pcmax,or a maximum transmit power allowed for the particular PA, P_(CMAX) _(_)_(PA) _(_) _(i). In this case, the WTRU may reduce some or all of thetransmit power levels across all or some of the UL CCs. For example, theWTRU may reduce the transmit power on at least some of the UL CCs by arelative amount. For example, the power reduction amount for a UL CC maybe relative to the total transmit power on the CC, which is the sum ofthe transmit power levels of the PUSCH and/or the PUCCH on the CC. Thetransmit power of the PUSCH and/or the PUCCH may be determinedindependently per channel and per CC according to Equation 1 for PUSCHand Equation 5 for PUCCH.

After the power reduction operation, the sum of all the power levelsacross all the CCs may be at least close to, and may equal the maximumWTRU allowed transmit power. The sum of all the power levels across allCCs may not exceed the maximum WTRU allowed transmit power.Alternatively, the power reduction factors used by the WTRU on the ULCCs may be configured by the eNB.

When the WTRU uses multiple UL CCs, the power reduction may be based ona priority of the channels on an individual UL CC where the priority maybe determined based on the type or requirements of each channel on eachCC. For example, if a PUCCH is transmitted on a UL CC, then the UL CCmay be scaled down last. The power of lower priority UL CCs is reducedbefore the power of the higher priority UL CCs. The WTRU may choose asubset of the UL CC's for UL transmission based on priority of the CCs,for example, choosing UL CCs with the highest priority. Some of lowerpriority UL CCs may be dropped first.

When using a subset of CCs, and PUSCH and PUCCH are simultaneouslytransmitted, a PUCCH transmission, particularly if it includes criticalfeedback information, such as an ACK/NACK in PDCCH or UCI on PUSCH, mayhave priority over a PUSCH transmission without UCI. The WTRU may choosea CC for power allocation based on which CC has an UL grant, requiresthe least required transmit power, the CC with the least pathloss or theCC that has a retransmitted data packet. Alternatively, the eNB maychoose the subset.

Once a subset of the CC's is selected, the WTRU may recalculate thepower levels for the physical channels on the CCs in the selectedsubset. If, after the UL CCs are selected, the WTRU power level is at orabove the maximum power limitation, then the WTRU may reduce the powerof at least some of the chosen CCs according to an appropriate andrelevant power reduction method. The physical channels on CCs that arenot selected may not be transmitted in the subframe. That is, thephysical channels on the non-selected CCs may be dropped.

If there are multiple CCs using separate PAs, there may be anassociation between the CCs and the PAs. For example, a set or subset ofcontiguous CCs may share a PA. The transmit power of the PUSCH and/orthe PUCCH on each CC may be computed independently per physical channelper CC according to Equation 1 for PUSCH and Equation 5 for PUCCH. TheWTRU may need to check whether there is any maximum power limitation,for example, CC-specific maximum power limitation, PA-specific, CC groupspecific maximum power limitation, and/or total maximum powerlimitation. The WTRU's top priority may be to comply with theCC-specific maximum power limitation (P_(CMAX)(k)) during the WTRU'sdetermination of the transmission power for the PUSCH and/or the PUCCH.Furthermore, when there is a simultaneous PUSCH and PUCCH transmissionon a CC, the CC-specific maximum power limitation is complied with usingany of the relevant CC-specific power reduction techniques describedherein.

After implementing the CC-specific maximum power limitation procedure,the WTRU may check to determine if the maximum power limitation of eachPA is violated such that the sum of the powers on all the individual CCssharing the PA exceeds the maximum PA allowed power. For example, forPA(i),

$P_{{{CMAX}\_ {PA}}{\_ i}} < {\sum\limits_{k \in {{{CC}\_ {PA}}{\_ i}}}\; {\left( {{P_{PUSCH}(k)} + {P_{PUCCH}(k)}} \right).}}$

If there is a violation of the maximum PA power limitation for a PA, theWTRU may comply with the limitation by applying a proper power reductiontechnique as described herein.

The WTRU may check whether the WTRU total maximum allowed transmit poweracross all the UL CCs, for example, P_(CMAX), is reached. If the maximumallowed transmit power across all the UL CCs is reached, the WTRU mayreduce some or all of the transmit power levels across some or all ofthe UL CCs according to a proper power reduction technique as describedherein, such that that the WTRU total maximum allowed transmit power isnot exceeded.

Since the PUSCH and the PUCCH can be transmitted at the same time, aswell as on non-contiguous RBs even on a single UL CC, the totaltransmitted signal waveform does not have the same properties as of asingle carrier frequency domain multiplex access (SC-FDMA) signal. Thismay result in an increase in the cubic metric (CM), or peak-to-averagepower ratio (PAPR), of the transmitted signal. The increased CM of thetwo simultaneous transmissions for the WTRU may need to meet linearityrequirements, such as error vector magnitude (EVM) and adjacent powerleakage power ratio (ACLR) requirements, for example. As the WTRUtransmit power for the PUSCH and PUCCH are controlled by an eNB, theWTRU may control the pathloss measurement and the WTRU may determinewhen not to exceed a maximum transmit power such as Pcmax, even in caseof using a single UL CC. Therefore, a back-off mechanism may beavailable to the WTRU to reduce the maximum transmit power based on theWTRU capabilities and/or as directed by the eNB.

The WTRU may determine power back-off as a function of the CM of thePUCCH/PUSCH signals. The eNB may adjust the maximum power based on theknown behavior of a specific WTRU or a generic WTRU. CM may be affectedprimarily by factors such as a number of non-contiguous radio bearers(RBs), modulation order, such as QPSK, 16QAM, 64QAM, and power ratios,for example, between PUSCH and PUCCH. As the power settings for PUSCHand PUCCH respectively are independent and dynamic, the ratio ofP_(PUSCH)(i) and P_(PUCCH)(i) varies in time, implying variable CM. CMmay vary in time.

When the WTRU uses a single UL CC, and PUSCH and PUCCH aresimultaneously transmitted, the transmit power of PUSCH and/or PUCCH oneach CC is computed independently per physical channel according toEquation 1 for PUSCH and Equation 5 for PUCCH. When the WTRU istransmitting on a single UL CC, P_(CMAX)(k) in both Equation 1 and 5 maybe equivalent to P_(CMAX). After computing the power levels of PUSCH andPUCCH, respectively, denoted by P_(PUSCH)(i) for PUSCH transmission andP_(PUCCH)(i) for PUCCH transmission in subframe i, if the sum of thepower levels is greater than a maximum WTRU allowed power such asP_(CMAX) (P_(PUSCH)(i)+P_(PUCCH)(i)>P_(CMAX)), the WTRU may reduce thepower of the channels based on channel priority first. Channel prioritymay be predefined. For example, if PUCCH is given greater priority thatthe PUSCH, pursuant to a predefined rule, the power of the PUSCH may bereduced before the power of the PUCCH. The PUSCH may be droppedcompletely if the reduced power of the PUSCH is less than a predefinedthreshold or a minimum transmit power. Furthermore, if there is a needto further reduce the power of the PUCCH, then the WTRU may reduce thepower to comply with the maximum transmit power limitation (i.e.,P_(CMAX)).

If P_(PUSCH)(i)+P_(PUCCH)(i)>P_(CMAX), then the transmit power for PUCCHmay be determined by Equation 5, set forth above. The transmit power forPUSCH is determined from the remaining available power, for example,P_(CMAX)−P_(PUCCH)(i) (subtract in linear)), as in the equation:

P _(PUSCH)(i)=min{(P _(CMAX) −P _(PUCCH)(i)),10 log₁₀(M _(PUSCH)(i))+P_(O) _(_) _(PUSCH)(j)+α(j)·PL+Δ_(TF)(i)+ƒ(i)}   (Equation 15).

If P_(PUSCH)(i) is less than a predefined value, for example, a minimumpower, then the PUSCH is dropped.

Alternatively, for a maximum power limitation, the respective transmitpower may be reduced equally as follows:

{tilde over (P)} _(PUSCH)(i)=P _(PUSCH)(i)−Δ(i) (dBm)  (Equation 16),

{tilde over (P)} _(PUCCH)(i)=P _(PUCCH)(i)−Δ(i) (dBm)  (Equation 17),

where Δ(i) is the power adjustment factor (in dB) in subframe i. TheWTRU may determine the power adjustment according to the equation:

$\begin{matrix}{{\Delta (i)} = {10*\; \log \; 10\left( {10^{\frac{P_{PUSCH}{(i)}}{10}} + 10^{\frac{P_{PUCCH}{(i)}}{10}} - 10^{\frac{P_{CMAX}}{10}}} \right){({dB}).}}} & \left( {{Equation}\mspace{14mu} 18} \right)\end{matrix}$

Alternatively, A(i) may be provided by higher layers, such as using alook up table or via semi static signaling. P_(PUSCH)(i) andP_(PUCCH)(i) represent the required transmit powers of PUSCH and PUCCHin subframe i, respectively.

In yet another alternative, Δ_(PUSCH)(i) and Δ_(PUCCH)(i) may beproportional to P_(PUSCH)(i) and P_(PUCCH)(i), respectively. Forexample,

$\begin{matrix}{{{\Delta_{PUSCH}(i)} \approx {\left( \frac{a*{P_{PUSCH}(i)}}{{P_{PUSCH}(i)} + {P_{PCSCH}(i)}} \right) \cdot {\Delta (i)}}},} & \left( {{Equation}\mspace{14mu} 19} \right) \\{{{\Delta_{PUSCH}(i)} \approx {\left( \frac{b*{P_{PUCCH}(i)}}{{P_{PUSCH}(i)} + {P_{PCSCH}(i)}} \right) \cdot {\Delta (i)}}},} & \left( {{Equation}\mspace{14mu} 20} \right)\end{matrix}$

where a and b are additional scaling factors and both a and b aregreater than or equal to zero (0). The terms a and b may be chosen sothat one channel is less than another channel. The terms may be adjustedso that one channel is given higher priority, or favored. The terms aand b may be calculated by the WTRU or be configured by the eNB andsignaled to the WTRU by higher layers. Alternatively, Δ_(PUSCH)(i) andΔ_(PUCCH)(i) may be provided by higher layers.

If either PUSCH or PUCCH alone exceeds P_(CMAX), the channel thatexceeds the maximum should be disproportionately reduced (or scaleddown). For example, let P_(PUSCH)(i)=10 and P_(PUCCH)(i)=2. Using areduction rule to reduce both by same relative amount results in, ifP_(CMAX)=10, then P_(PUSCH)(i)=(10/12)*P_(PUSCH)(i) andP_(PUCCH)(i)=(10/12)*P_(PUCCH)(i). SinceP_(PUSCH)(i)+P_(PUCCH)(i)=Pmax=10, both may be reduced by ⅙-th power.However, if P_(CMAX)=8, then P_(PUSCH)(i)=(8/10)*(P_(PUSCH)(i)−2) andP_(PUCCH)(i)=(8/10)*P_(PUCCH)(i). AsP_(PUSCH)(i)+P_(PUCCH)(i)=P_(CMAX)=8, the PUSCH transmit power isreduced by a larger percentage than the PUCCH.

There may be different reduction rules based on the type of controlinformation on PUCCH. For example, reduction may be shared equallybetween PUSCH and PUCCH, if PUCCH is carrying CQI, but if it is carryingACK/NACK, the PUSCH may incur more power reduction than the PUCCH. Forexample, if P_(PUSCH)(i)+P_(PUCCH)(i)>P_(CMAX), then:

{tilde over (P)} _(PUSCH)(i)=P _(PUSCH)(i)−Δ_(PUSCH)(i) (dBm); and

{tilde over (P)} _(PUCCH,CQI)(i)=P _(PUCCH)(i)−Δ_(PUSCH)(i) (dBm); or

{tilde over (P)} _(PUCCH,CQI)(i)=P _(PUCCH)(i)−Δ_(PUCCH,CQI)(i) (dBm);and

{tilde over (P)} _(PUCCH,ACK)(i)=P _(PUCCH)(i)−Δ_(PUCCH,ACK)(i) (dBm),

where Δ_(PUSCH)(i), Δ_(PUCCH,CQ)(i), and Δ_(PUCCH,ACK)(i) are the poweradjustment factors for the PUSCH, CQI on PUCCH, and ACK/NACK on PUCCH,respectively, in subframe i whereΔ_(PUSCH)(i)>Δ_(PUCCH,CQ)(i)>Δ_(PUCCH,ACK)(i).

Reduction rules may depend on multiple input/multiple output (MIMO) modeor hybrid automated retransmission request (HARQ) retransmission number,for example. For a HARQ retransmission, then the PUSCH may perform lesspower reduction as the number of retransmissions increases.

Maximum transmit power limit, for example, P_(CMAX) may be backed-off bythe WTRU based on a preconfigured rule. The WTRU may adjust P_(CMAX) asa function of increased cubic metric (CM) of the simultaneousPUCCH/PUSCH waveform, or any method that estimates the maximum power andmeets ACLR/EVM requirements. The increased CM, (delta_CM), is therequired power back-off, or allowed maximum power back-off, as afunction of the number of non-contiguous clusters, PSUCH modulationtype, and the power ratio between PUSCH and PUCCH. Each WTRU maydetermine the increased CM of each UL transmission, which is based on agiven UL grant, and then back-off P_(CMAX) by subtracting delta_CM fromP_(CMAX) or maximum WTRU power for the WTRU power class, denoted byP_(UMAX), as required. The WTRU may calculate the delta_CM of UL signalsand may change P_(CMAX) or P_(UMAX) dynamically, perhaps as fast asevery subframe.

Alternatively, a parameter look-up table showing delta_CM may besignaled to the WTRU from an eNB. The table may use an index thatcorresponds to a number of discontinuities in RB allocation, a number ofdiscontinuities for a given PA, PSUCH modulation type, the power ratiobetween PUSCH and PUCCH, the precoding used, and other relevantparameters. Table 2 is an example of a delta_CM look-up table.

TABLE 2 delta_cm power ratio number of modu- between discontinuitiesnumber of lation PUSCH in RB discontinuities type for and Index, kdelta_cm allocation for a given PA PUSCH PUCCH 1 X₁ dB 2 1 QPSK 1 2 X₂dB 3 1 QPSK 1 3 X₃ dB 4 1 QPSK 2 4 X₄ dB 5 1 QPSK 2 5 X₅ dB 3 2 QPSK 3 6X₆ dB 4 3 QPSK 4 7 X₇ dB 5 3 QPSK 6 8 X₈ dB 2 1 16QAM 1 9 X₉dB 3 1 16QAM1 10 X₁₀ dB 4 1 16QAM 2 11 X₁₁ dB 3 2 16QAM 4 12 X₁₂ dB 4 2 16QAM 5 13X₁₃ dB 2 1 64QAM 1 14 X₁₄ dB 3 1 64QAM 1 15 X₁₅ dB 3 2 64QAM 2 16 X₁₆ dB3 3 64QAM 4

DL signaling may be designed to support relevant parameters, such as adelta_CM table and a delta_CM index, for maximum WTRU power settings. DLsignaling may also be designed to support a lookup table for PHreporting. The WTRU may check ACLR/EVM/CM requirements and maximumpower, and perform additional back-off, if required, after performingpower control using the delta_CM parameter.

The eNB includes the details of the allocation for both PUSCH and PUCCH.Rather than use a look-up table for back-off, the eNB may estimate theCM. Accordingly, P_(CMAX) can be lowered when an eNB makes an UL grantto a WTRU for simultaneous PUCCH and PUSCH transmission. The eNB canmanage the power ratio of PUCCH and PUSCH as well. As a rule, the PUCCHpower level may not be reduced, or scaled down. The PUSCH power may bebacked-off, as required, to maintain linearity, especially in case ofmaximum power limitation Alternatively, PUSCH power may be not reducedor scaled down.

A maximum power value, for example, P_(CMAX) may accommodate a worstcase condition, even though many transmission cases would have morefavorable power requirements and limitation. Maximum power in aparticular power class, with simultaneous PUSCH and PUCCH transmissionmay be defined by a look up table. Table 3 is an example of a look-uptable for maximum power.

TABLE 3 Power Rating P_(CMAX) (dB) Ratio (dB) where Index PUSCH/PUCCHPcmax = 23 1 Ratio >10 Pcmax - 1 2 10> ratio >5 Pcmax - 2 3 5> ratio >−5Pcmax - 3 4 −5> ratio >−10 Pcmax - 4 5 −10> ratio Pcmax - 5P_(CMAX) may also be a function of other variables, including separationin frequency and/or number of discontinuities in resource allocation.

TPC commands may be accumulated. However, if a WTRU reaches P_(CMAX)after summing up the powers of PUSCH and PUCCH, respectively, positiveTPC commands for PUSCH and PUCCH may not be accumulated. Similarly, ifthe calculated transmit power of PUSCH exceeds P_(CMAX), positive TPCcommands for PUSCH may not be accumulated. However, if the calculatedtransmit power of PUCCH exceeds P_(CMAX), positive TPC commands forPUCCH may be accumulated.

TPC commands may have a unique interpretation when they correspond tosimultaneous PUCCH and PUSCH transmission, both with and without SRS andnon-contiguous PUSCH. TPC commands may have a large enough magnitude sothat the eNB may reduce power by a larger step for UL transmission withlarger CM. Table 4 is an example of a TPC command table.

TABLE 4 TPC Commands Absolute TPC Absolute δ_(pucch+pusch) Commandδ_(PUSCH) [dB] Accumulated [dB] only Field in Accumulated only DCIδ_(pucch+pusch) DCI DCI format 0/3 δ_(PUSCH) [dB] format 0 [dB] format 00 −1 −4 −2 −5 1 0 −1 −1 −2 2 1 1 0 0 3 3 4 2 3If a WTRU has reached the configured maximum WTRU transmitted power,P_(CMAX), positive accumulation TPC commands may not be accumulated.However, if P_(UMAX) is reached for a particular subframe where P_(UMAX)is the maximum WTRU power for the WTRU power class but P_(CMAX) has notbeen reached, TPC commands may be accumulated. If P_(CMAX) is reachedfor a particular subframe, but P_(UMAX) has not, then TPC commands maynot be accumulated. If P_(CMAX) is reached for a particular subframe,but the corresponding allocation is non-contiguous, TPC commands may beaccumulated. If P_(UMAX) is reached for a particular subframe, but thecorresponding allocation is non-contiguous, then TPC commands may beaccumulated. If P_(CMAX) is reached for a particular subframe, but thecorresponding allocation is simultaneous with PUCCH, then TPC commandsmay be accumulated. If accumulation TPC commands for PUCCH are includedin PDCCH, then positive TPC commands for PUCCH may not be accumulated.

If P_(UMAX) or P_(CMAX) is reached for a particular subframe, but thecorresponding allocation is simultaneous with PUSCH, then TPC commandsmay be accumulated. In addition, if the WTRU has reached minimum powerfor PUSCH or PUCCH, negative TPC commands for the corresponding channelsmay not be accumulated.

If the WTRU has reached the configured WTRU transmitted power and ifaccumulation TPC commands for PUSCH are included in PDCCH, positive TPCcommands for PUSCH may not be accumulated. If accumulation TPC commandsfor PUSCH are included in the PDCCH, PUSCH may not be accumulated.

When the sum of the ideally computed powers exceeds P_(CMAX), theindividual power levels may be reduced by separate offsets, Δ_(PUSCH)(i)and Δ_(PUCCH)(i). Each offset may be calculated in each UL subframe bythe WTRU or provided by higher layers, according to its own requirement,but satisfying the equation {tilde over (P)}_(PUSCH) (i)+{tilde over(P)}_(PUCCH)(i)=P_(cmax).

The reliability requirements for PUCCH and PUSCH are typicallydifferent. Therefore, careful setting of the power levels is desirable,particularly if the sum of the ideally computed powers exceeds P_(CMAX).

Under certain conditions, such as maximum power limitation, for example,the WTRU may be configured to have concurrent PUSCH/PUCCH transmissionor to include uplink control information (UCI) in PUSCH. IfP_(PUSCH)(i)+P_(PUCCH)(i)>P_(CMAX), then the WTRU may carry UCI over thePUSCH. The eNB may configure the WTRU through, for example, higher layersignaling or L1/L2 signaling, whether to carry UCI over PUSCH. Atoggling bit may be used in the PDCCH that indicates a particular DCIformat. The eNB may determine the configuration based on, for example,power headroom (PH) reporting from the WTRU.

For example, a WTRU may be configured to carry UCI on the PUSCH. IfPH>γ, where γ represents a predefined threshold for the configuration,the eNB may reconfigure the WTRU through higher layer signaling, L1/L2signaling or toggling a bit, to go back to concurrent PUCCH and PUSCHtransmission.

Alternatively, the WTRU may autonomously determine which controlsignaling scheme may be used in a subframe. For instance, if P_(PUSCH)(i)+P_(PUCCH)(i)<P_(CMAX)−γ, concurrent PUSCH/PUCCH transmissions may beused. The WTRU's determination may be based on the transmit poweravailable for PUCCH. For example, if {tilde over(P)}_(PUCCH)(i)−P_(PUCCH)(i)>η, where η represents the threshold for amaximum PUCCH power reduction factor, concurrent PUSCH/PUCCHtransmission may be used. The term {tilde over (P)}_(PUCCH)(i) is thetransmit power of PUCCH after power reduction, if any, where {tilde over(P)}_(PUCCH)(i) can be calculated by a transmit power reduction method.

An eNB may perform blind detecting and/or decoding for extracting UCI.If the sum of the PUSCH and PUCCH transmission power reaches a maximumallowed power by a threshold β₁, the WTRU may switch to anon-simultaneous PUSCH/PUCCH transmission mode if the sum of the PUSCHand PUCCH transmission power reaches the maximum allowed power by athreshold β₂.

If UL L1/2 control signaling, such as UCI, is time multiplexed with dataon the PUSCH, such as UCI transmission, the transmit power may be keptconstant over the subframe. P_(PUSCH)(i) may be determined using a poweroffset as:

{tilde over (P)} _(PUSCH)(i)=P _(PUSCH)(i)+ε  (Equation21),

where ε is the power offset which can be configured via higher layersignaling. ε may be function of the offset between the code rate for thecontrol part and the modulation and code rate used for the data part.

Alternatively, in order to increase coding gains for either the controlpart or the data part, when there is SRS configured to be transmitted inthe same subframe, the WTRU may use the discreet Fouriertransform-orthogonal frequency domain multiplex (DFT-OFDM) symbol, forexample, the last symbol in the subframe, for either the control part orthe data part rather than the SRS. Alternatively, either the controlpart or the data part is punctured into a frequency part of the SRSregion where the frequency part corresponds to that used for PUSCH inthe other DFT-OFDM symbols.

Depending on the power headroom, CM increment, reliability requirementsand priority for control information, such as ACK/NACK, CQI and SR, forexample, and data, respectively, the WTRU may autonomously determine acombination of control and/or data channel types to be transmitted in asubframe. For example, if PH<−μ₁ (dB), the WTRU may drop either PUSCH orPUCCH and give the full power to the other channel. Otherwise, if PH<−μ₂(dB), the WTRU may drop CQI and/or SR and split the maximum power intoPUCCH and PUSCH where PUCCH carries ACK/NACK, for example, and perhapsother feedback signals.

If PH<−μ₃ (dB), the WTRU may not drop any channels and may transmit bothPUCCH and PUSCH using one of the power reduction methods disclosedherein. The terms μ₁, μ₂, μ₃ are cell and/or WTRU specific parameterswhere μ_(l)>μ₂>μ₃>0.

The eNB may require information about the channel combination in a givensubframe. The WTRU may explicitly inform the eNB of the combinationinformation used in the subframe via, for example, L1/2 signaling with 1or 2 bits on an UL channel such as the PUCCH, for example.Alternatively, separate control signaling may be used in the UL. By wayof another alternative, the eNB may determine the channel combination inuse in the given subframe by, for example, performing blind detectionand/or decoding to extract and/or decode the control information.

The eNB may determine the combination of channel types to be transmittedin a subframe. This may be based on power headroom. The eNB may signalthe resulting combination to the WTRU via higher layers or on the PDCCHwith a particular DCI format, for example. The transmit power settingfor PUSCH and PUCCH, respectively, may be written as:

P _(PUSCH)(i)=min{P _(CMAX,PUSCH),10 log₁₀(M _(PUSCH)(i))+P _(O) _(_)_(PUSCH)(j)+α(j)·PL+Δ_(TF)(i)+ƒ(i)}   (Equation 22), and

P _(PUCCH)(i)=min{P _(CMAX,PUCCH) ,P ₀ _(_) _(PUCCH)+PL+h(n _(CQI) ,n_(HARQ))+Δ_(F) _(_) _(PUCCH)(F)+g(i)}   (Equation 23).

The transmit power of one of the PUSCH or the PUCCH may be below maximumpower, while the transmit power of the other may be above its maximum.The extra power in the one channel may be added to the other.Alternatively, the power settings for PUSCH and PUCCH may be setjointly. The WTRU may calculate the transmit power for PUSCH. Thetransmit power for PUCCH may then be offset to the resulting PUSCHtransmit power by an offset factor, φ_(PUCCH), as in the equationP_(PUCCH)(i)=P_(PUSCH)(i)+φ_(PUCCH), where φ_(PUCCH) may be configuredby higher layers and depend on the modulation type and coding rate usedfor the UL subframe.

If the PUSCH also includes an SRS, and the PSUCH is simultaneouslytransmitted with the PUCCH, SRS may be time multiplexed with PUSCH, butfrequency multiplexed with PUCCH in last symbol. The SRS may otherwisebe punctured by the PUSCH. In either case, the WTRU may apply twoseparated back-off procedures.

Power headroom (PH) may be defined per UL CC as:

PH(i,k)=P _(CMAX)−{10 log₁₀(M _(PUSCH)(i,k))+P _(O) _(_)_(PUSCH)(j,k)+α(j,k)·PL(k)+Δ_(TF)(i,k)+ƒ(i,k)}   (Equation24),

where PH(i,k) is the WTRU PH valid for subframe i on UL CC(k).

Alternatively, PH may be defined per UL CC as:

PH(i,k)=P _(CMAX)(k)−{10 log₁₀(M _(PUSCH)(i,k))+P _(O) _(_)_(PUSCH)(j,k)+α(j,k)·PL(k)+Δ_(TF)(i,k)+ƒ(i,k)}   (Equation 25).

PH reporting may be configurable. The WTRU transmit power on a certainCC may be different from that on other CCs due to different pathlossesand channel configurations. The WTRU may transmit to the eNB a PH reportper CC. In certain cases, for example, when the aggregated carriers arecontiguous, a wideband PH report may be transmitted. The eNB couldconfigure the WTRU to report the PH.

The WTRU may report a CC specific PH. The CC specific PH may be roundedto the closest value in the range in dB, with steps of 1 dB, forexample, and delivered by the physical layer to higher layers.

The WTU may alternatively report a CC group specific PH report. The WTRUmay configure the groups of CCs in accordance with instructions from theeNB and compute the PH for a group of CCs as follows:

$\begin{matrix}{{{{PH}\left( {i,k_{G}} \right)} = {P_{CMAX} - {10\log_{10}\left\{ {\sum\limits_{k \in k_{G}}\; 10^{\frac{\begin{matrix}{{{10\; {\log_{10}{({M_{PUSCH}{({i,k})}})}}} + {P_{O\_ {PUSCH}}{({j,k})}} +}\;} \\{{{a{({j,k})}} \cdot {{PL}{(k)}}} + {\Delta_{TF}{({i,k})}} + {f{({i,k})}}}\end{matrix}}{10}}} \right\}}}},} & \left( {{Equation}\mspace{14mu} 26} \right)\end{matrix}$

where k_(G) represents the k^(th) CC group. P_(CMAX) may be replacedwith a value for maximum transmit power allowable for each CC group,which may be signaled from the eNB. Alternatively, the WTRU maydetermine a maximum transmit power for each CC group, according to howUL CCs in a CC group are associated with the WTRU RF chain, includingthe PA. For example, when UL CCs in a CC group share a PA in the WTRU,then the maximum power for the CC group may be the maximum allowed powerfor the PA.

The WTRU may alternatively report a wideband PH. The calculated PUSCHtransmit power levels on all the CCs are accounted for the PH reportingas:

$\begin{matrix}{{{{PH}_{WB}(i)} = {P_{CMAX} - {10\; \log_{10}\left\{ {\overset{K}{\sum\limits_{k = 1}}\; 10^{\frac{\begin{matrix}{{{10\; {\log_{10}{({M_{PUSCH}{({i,k})}})}}} + {P_{O\_ {PUSCH}}{({j,k})}} +}\;} \\{{{a{({j,k})}} \cdot {{PL}{(k)}}} + {\Delta_{TF}{({i,k})}} + {f{({i,k})}}}\end{matrix}}{10}}} \right\} ({dB})}}},} & \left( {{Equation}\mspace{14mu} 27} \right)\end{matrix}$

where PH_(WB)(i) is the wideband WTRU PH valid for subframe i. The rangeof PH_(WB)(i) may be different than that for the CC specific or CC groupspecific PH reporting.

The eNB may send configuration information to the WTRU as to which PHreporting format the WTRU may use. Alternatively, the WTRU mayautonomously determine the UL CCs on which it will send a PH report.When the WTRU reports the PH, an associated CC indictor may be senttogether with the PH report. For example, the WTRU may be configured tosend a wideband PH report, but the WTRU may detect that the calculatedtransmit power on a CCs exceeds or is below a predefined threshold Inaddition to the wideband PH reporting, the WTRU may send a PH report onthe detected CCs along with an associated CC indicator.

The WTRU PH reporting may be based on a triggering mechanism. Forexample, when a CC specific PH value is less than a threshold, the WTRUmay report the corresponding PH value to the eNB. In either CC specificPH or CC group specific PH reporting, whether the PH report correspondsto a CC or CC group may be indicated by a CC group indicator. Theindicator is sent to the eNB along with the corresponding PH values.

An eNB may configure a WTRU to send a PH report based on a PUCCH eventhough there is no PUSCH transmission in a particular subframe on a CC.The WTRU may send a PH report based on PUSCH transmission only, whenthere is no simultaneous PUSCH/PUCCH transmission or no PUCCHtransmission on an UL CC.

The WTRU may send a PH report based on PUCCH transmission only. This maybe used for simultaneous PUSCH/PUCCH transmission on a UL CC. The WTRUmay send a PH report based on both PUSCH and PUCCH transmissions. Thismode may be used in the event of simultaneous PUSCH/PUCCH transmissionon a UL CC.

When simultaneous PUSCH and PUCCH transmission occurs in a subframe i onUL CC(k), the CC specific WTRU PH for the subframe on the CC(k), forcombined PUSCH and PUSCH power headroom reporting (PHR), the reported PHmay be given by the equation:

$\begin{matrix}{{{PH}\left( {i,k} \right)} = {P_{CMAX} - {10\mspace{11mu} {{\log_{10}\left( {10^{\frac{\begin{matrix}{\{{{10\; {\log_{10}{({M_{PUSCH}{({i,k})}})}}} + {P_{O\_ {PUSCH}}{({j,k})}} +}\;} \\{{{{a{({j,k})}} \cdot {{PL}{(k)}}} + {\Delta_{TF}{({i,k})}} + {f{({i,k})}}}\}}\end{matrix}}{10}} + 10^{\frac{\begin{matrix}{\{{{P_{O\_ {PUCCH}}{(k)}} + {{PL}{(k)}} + {h{({n_{CQI},n_{HARQ},k})}} +}} \\{{{\Delta_{F\_ {PUCCH}}{(F)}} + {g{({i,k})}}}\}}\end{matrix}}{10}}} \right)}.}}}} & \left( {{Equation}\mspace{14mu} 28} \right)\end{matrix}$

Alternatively, the reported PH may be expressed as:

$\begin{matrix}{{{PH}\left( {i,k} \right)} = {{P_{CMAX}(k)} - {10\mspace{11mu} {{\log_{10}\left( {10^{\frac{\begin{matrix}{\{{{10\; {\log_{10}{({M_{PUSCH}{({i,k})}})}}} + {P_{O\_ {PUSCH}}{({j,k})}} +}\;} \\{{{{a{({j,k})}} \cdot {{PL}{(k)}}} + {\Delta_{TF}{({i,k})}} + {f{({i,k})}}}\}}\end{matrix}}{10}} + 10^{\frac{\begin{matrix}{\{{{P_{O\_ {PUCCH}}{(k)}} + {{PL}{(k)}} + {h{({n_{CQI},n_{HARQ},k})}} +}} \\{{{\Delta_{F\_ {PUCCH}}{(F)}} + {g{({i,k})}}}\}}\end{matrix}}{10}}} \right)}.}}}} & \left( {{Equation}\mspace{14mu} 29} \right)\end{matrix}$

Alternatively, the PH may be computed and reported individually forPUSCH and PUCCH and may be equal to P_(CMAX) (or P_(CMAX)(k)) reduced,or subtracted by calculated transmit powers of the PUSCH and PUCCH,respectively, as indicated in the equations:

$\begin{matrix}{{{{PH}_{PUSCH}\left( {i,k} \right)} = {{P_{CMAX}(k)} - \left( {{10\mspace{11mu} {\log_{10}\left( {M_{PUSCH}\left( {i,k} \right)} \right)}} + {P_{O\_ {PUSCH}}\left( {j,k} \right)} + {{\alpha \left( {j,k} \right)} \cdot {{PL}(k)}} + {\Delta_{TF}\left( {i,k} \right)} + {f\left( {i,k} \right)}} \right)}},\; {and}} & \left( {{Equation}\mspace{14mu} 30} \right) \\{{{{PH}_{PUCCH}\left( {i,k} \right)} = {{P_{CMAX}(k)} - \left( {{P_{O\_ {PUCCH}}(k)} + {{PL}(k)} + {h\left( {n_{CQI},n_{HARQ},k} \right)} + {\Delta_{F\_ {PUCCH}}(F)} + {g\left( {i,k} \right)}} \right)}},} & \left( {{Equation}\mspace{14mu} 31} \right)\end{matrix}$

where PH_(PUSCH)(i,k) and PH_(PUCCH)(i,k) represent the PH reports forPUSCH and PUCCH, respectively. In Equation 30 and Equation 31,respectively, P_(CMAX)(k) may be replaced with P_(CMAX).

In yet another alternative, the calculated WTRU transmit power for PUSCHin subframe i on UL CC(k) in linear scale may be represented by theequation:

$\begin{matrix}{{P_{{calc}\_ {PUSCH}}\left( {i,k} \right)} = 10^{\begin{matrix}{({({{10\mspace{11mu} {\log_{10}{({M_{PUSCH}{({i,k})}})}}} + {{P_{O\_ {PUSCH}}{({j,k})}}\mspace{11mu} {{\alpha {({j,k})}}\; \cdot}}}}} \\{{{{{{PL}{(k)}} + {\Delta_{TF}{({i,k})}} + {f{({i,k})}}})}/10})}\end{matrix}}} & \left( {{Equation}\mspace{14mu} 32} \right)\end{matrix}$

Similarly the calculated WTRU transmit power for PUCCH in subframe i onUL CC(k) in linear scale may be represented by the equation:

$\begin{matrix}{{P_{{calc}\_ {PUCCH}}\left( {i,k} \right)} = 10^{{({{({{P_{O\_ {PUCCH}}{(k)}}\; + {{PL}{(k)}} + {h{({{n_{{CQI},}n_{HARQ}},k})}} + {\Delta_{F\_ {PUCCH}}{(F)}} + {g{({i,k})}}})}/10})}.}} & \left( {{Equation}\mspace{14mu} 33} \right)\end{matrix}$

In order to report PH for PUSCH alone, PH for PUCCH alone, or PH forPUSCH and PUCCH combined, PH for subframe i and CC(k) may be expressedas:

PH(i,k)=10 log(Pcmax/Pcalc_pusch) [dB];

PH(i,k)=10 log(min(Pcmax,Pcm)/Pcalc_pusch) [dB];

PH(i,k)=10 log(Pcmax/Pcalc_pucch) [dB];

PH(i,k)=10 log(min(Pcmax,Pcm)/Pcalc_pucch) [dB];

PH(i,k)=10 log(min(Pcmax,Pcm)/(Pcalc_pusch+Pcalc_pucch))[dB]; or

PH(i,k)=10 log(Pcmax/(Pcalc_pusch+Pcalc_pucch)) [dB]

The term Pcm denotes power at which EVM/ACLR is violated and is amaximum power value that reflects a required power back-off due toincreased CM. Pcm may be estimated by the WTRU for UL transmission inthe subframe of interest or may be estimated according to a lookup tablebased on the transmission details including, for example, PUCCH power,PUSCH power, modulations, and number of discontinuities. The lookuptable may be signaled by higher layers or implemented in the eNB. In theabove equations, Pcmax may be replaced by Pcmax(k).

Each type of PH may be computed and reported as appropriate. The type ofPH reported may be determined by higher layer signaling. A schedule foreach type may be setup by higher layer signaling or the type of PHreport may be a function of the PDCCH.

CM may also be accounted for in PHR calculation. An eNB may haveinformation regarding the details of the allocation for both PUSCH andPUCCH. The eNB may estimate the CM, but not necessarily the precisereduction in P_(CMAX) or P_(CMAX)(k) required.

A WTRU may transmit SRS in configured SRS subframes where SRS may beused for UL scheduling at the eNB. The SRS transmit power may follow thePUSCH transmit power, compensating for the bandwidth of the SRStransmission. A WTRU may not transmit SRS when the computed transmitpower of SRS exceeds P_(CMAX) or P_(CMAX)(k)+γ_(SRS) where γ_(SRS) is athreshold which is provided by higher layers.

The WTRU may not transmit SRS when SRS and PUSCH transmissions coincidein the same subframe and the transmit power of PUSCH for the givensubframe exceeds P_(CMAX) or P_(CMAX)(k))+γ_(PUSCH). The WTRU may usethe last OFDM symbol for the transmission of PUSCH as well. Furthermore,the WTRU may not transmit SRS with simultaneous PUSCH/PUCCHtransmission, when SRS and PUSCH/PUCCH transmissions coincide in thesame subframe and the sum of the transmit powers of PUSCH and PUCCH forthe given subframe exceeds P_(CMAX) or P_(CMAX)(k)+γ_(PUSCH) _(_)_(PUCCH), where γ_(PUSCH) _(_) _(PUCCH) is a threshold which is providedby higher layers. The WTRU may use the last OFDM symbol for thesimultaneous PUSCH/PUCCH transmission.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

1.-18. (canceled)
 19. A method of determining a power headroom (PH) in awireless transmit/receive unit (WTRU), the method comprising:transmitting, simultaneously, a physical uplink shared channel (PUSCH)with a physical uplink control channel (PUCCH) on at least one ofcarrier (k) on one or more subframes (i); identifying a maximum WTRUtransmit power on an uplink carrier (k); calculating PH (i,k) as adifference between the maximum WTRU transmit power on the uplink carrier(k) and a logarithmic function; and summing, as a part of thelogarithmic function, a first expression and a second expression, thefirst expression including: a bandwidth factor: M_(PUSCH)(i, k), anopen-loop component: P_(O) _(_) _(PUSCH)(j,k)+α(j, k)*PL(k), (j) beingan uplink transmission parameter, and a closed loop component, theclosed-loop component including a carrier specific modulation and codingscheme offset: Δ_(TF)(i,k), the second expression including a pathlossestimate for the uplink carrier (k): PL(k), a PUCCH format dependentvalue, and a PUCCH power control adjustment function: g(i,k).
 20. Themethod of claim 19, further comprising: rounding the PH (i,k) to aclosest value in a range in dB, in steps of 1 dB.
 21. The method ofclaim 19, wherein the PH (i,k) is calculated at a physical layer of theWTRU.
 22. The method of claim 21, further comprising: delivering the PH(i,k) to one or more layers of the WTRU higher than the physical layer.23. The method of claim 19, wherein the first expression furtherincludes a closed-loop function: ƒ(i, k).
 24. A wirelesstransmit/receive unit (WTRU), comprising: a memory; a transmitter, thetransmitter configured at least to: transmit, simultaneously, a physicaluplink shared channel (PUSCH) with a physical uplink control channel(PUCCH) on at least one of carrier (k) on one or more subframes (i); anda processor, the processor configured at least to: identify a maximumWTRU transmit power on an uplink carrier (k); calculate a power headroom(PH) (i,k) as a difference between the maximum WTRU transmit power onthe uplink carrier (k) and a logarithmic function; and sum, as a part ofthe logarithmic function, a first expression and a second expression,the first expression including: a bandwidth factor: M_(PUSCH)(i, k), anopen-loop component: P_(o) _(_) _(PUSCH)(j,k)+α(j, k)*PL(k), (j) beingan uplink transmission parameter, and a closed loop component, theclosed-loop component including a carrier specific modulation and codingscheme offset: Δ_(TF)(i,k), the second expression including a pathlossestimate for the uplink carrier (k): PL(k), a PUCCH format dependentvalue, and a PUCCH power control adjustment function: g(i,k).
 25. TheWTRU of claim 24, wherein the processor is further configured to: roundthe PH (i,k) to a closest value in a range in dB, in steps of 1 dB. 26.The WTRU of claim 24, wherein the processor is further configured tocalculate PH (i,k) at a physical layer of the WTRU.
 27. The WTRU ofclaim 26, wherein the processor is further configured to: deliver the PH(i,k) to one or more layers of the WTRU higher than the physical layer.28. The WTRU of claim 24, wherein the processor is further configuredsuch that the first expression further includes a closed-loop function:ƒ(i, k).
 29. A method of determining a power headroom (PH) in a wirelesstransmit/receive unit (WTRU), the method comprising: transmitting aphysical uplink shared channel (PUSCH) on at least one of a plurality ofcarriers (k) on one or more subframes (i); identifying a maximum WTRUtransmit power on an uplink carrier (k); calculating PH (i,k) as adifference between the maximum WTRU transmit power on the uplink carrier(k) and an expression, the expression including: a bandwidth factor:M_(PUSCH)(i, k), an open-loop component: P_(o) _(_) _(PUSCH)(j,k)+α(j,k)*PL(k), (j) being an uplink transmission parameter, and a closed-loopcomponent, the closed loop component including a carrier specificmodulation and coding scheme offset: Δ_(TF)(i,k); and summing, as partof the expression, the bandwidth factor, the open-loop component, andthe closed-loop component.
 30. The method of claim 29, furthercomprising: rounding the PH (i,k) to a closest value in a range in dB,in steps of 1 dB.
 31. The method of claim 29, wherein the PH (i,k) iscalculated at a physical layer of the WTRU.
 32. The method of claim 31,further comprising: delivering the PH (i,k) to one or more layers of theWTRU higher than the physical layer.
 33. The method of claim 29, whereinthe expression further includes a closed-loop function: ƒ(i, k).
 34. Awireless transmit/receive unit (WTRU), comprising: a memory; atransmitter, the transmitter configured at least to: transmit a physicaluplink shared channel (PUSCH) on at least one of a plurality of carriers(k) on one or more subframes (i); and a processor, the processorconfigured at least to: identify a maximum WTRU transmit power on anuplink carrier (k); calculate a power headroom (PH) (i,k) as adifference between the maximum WTRU transmit power on the uplink carrier(k) and an expression, the expression including: a bandwidth factor:M_(PUSCH)(i, k), an open-loop component: P_(o) _(_) _(PUSCH)(j,k)+α(j,k)*PL(k), (j) being an uplink transmission parameter, and a closed-loopcomponent, the closed loop component including a carrier specificmodulation and coding scheme offset: Δ_(TF)(i,k); and sum, as part ofthe expression, the bandwidth factor, the open-loop component, and theclosed-loop component.
 35. The WTRU of claim 34, wherein the processoris further configured to: round the PH (i,k) to a closest value in arange in dB, in steps of 1 dB.
 36. The WTRU of claim 34, wherein theprocessor is further configured to calculate PH (i,k) at a physicallayer of the WTRU.
 37. The WTRU of claim 36, wherein the processor isfurther configured to: deliver the PH (i,k) to one or more layers of theWTRU higher than the physical layer.
 38. The WTRU of claim 34, whereinthe processor is further configured such that the expression furtherincludes a closed-loop function: ƒ(i, k).